Hepatoprotective Actions of Ascorbic Acid, Alpha Lipoic Acid and Silymarin or Their Combination Against Acetaminophen-Induced Hepatotoxicity in Rats.

Background and objectives: Ascorbic acid, alpha lipoic acid (ALA) and silymarin are well-known antioxidants that have hepatoprotective effects. This study aims to investigate the effects of these three compounds combined with attenuating drug-induced oxidative stress and cellular damage, taking acetaminophen (APAP)-induced toxicity in rats as a model both in vivo and in vitro. Materials and Methods: Freshly cultured primary rat hepatocytes were treated with ascorbic acid, ALA, silymarin and their combination, both with and without the addition of APAP to evaluate their in vitro impact on cell proliferation and mitochondrial activity. In vivo study was performed on rats supplemented with the test compounds or their combination for one week followed by two toxic doses of APAP. Results: Selected liver function tests and oxidative stress markers including superoxide dismutase (SOD), malondialdehyde (MDA) and oxidized glutathione (GSSG) were detected. The in vivo results showed that all three pretreatment compounds and their combination prevented elevation of SOD and GSSG serum levels indicating a diminished burden of oxidative stress. Moreover, ascorbic acid, ALA and silymarin in combination reduced serum levels of liver enzymes; however, silymarin markedly maintained levels of all parameters to normal ranges. Silymarin either alone or combined with ascorbic acid and ALA protected cultured rat hepatocytes and increased cellular metabolic activity. The subjected agents were capable of significantly inhibiting the presence of oxidative stress induced by APAP toxicity and the best result for protection was seen with the use of silymarin. Conclusions: The measured liver function tests may suggest an augmented hepatoprotection of the combination preparation than when compared individually.

Antioxidative stress effects of vitamins C, E, and B12, and their combination can protect the liver against acetaminophen-induced hepatotoxicity in rats.

BACKGROUND: Several vitamins, including C, E, and B12, have been recognized as antioxidants and have shown hepatoprotective effects against the hepatotoxicity caused by acetaminophen (APAP) overdose. The current investigation aims to study the effect of these vitamins and their combination in protecting the liver from APAP hepatotoxicity in rats. MATERIALS AND METHODS: An in vitro model of freshly isolated rat hepatocytes was utilized for assessing hepatocyte mitochondrial activity conducted by cell proliferation assay (MTT). The isolated hepatocytes were treated with vitamin C, vitamin E, vitamin B12 and their combination, with and without further addition of toxic concentrations of APAP. In addition, an in vivo experiment was carried out on Sprague Dawley rats treated intraperitoneally for 8 days with emulsions of the vitamins or their combination prior to injecting them with APAP. RESULTS: In vitro results showed that vitamins C and B and the combination preparation significantly increased the percentage of hepatocyte mitochondrial activity, both with and without the addition of APAP (P<0.01). The mitochondrial activity in the isolated cultured hepatocytes was further enhanced with APAP addition. In vivo, the vitamins and their combination effectively reduced APAP-induced serum liver enzymes levels, namely ALT, AST, and ALP, and also attenuated oxidative stress and lipids peroxidation confirmed by the results of glutathione, superoxide dismutase, and maloondialdehyde. CONCLUSION: Pretreatment with vitamins C, E, B12, or their combination was found to be beneficial in preventing in vivo hepatic oxidative stress induced by APAP overdose. Vitamin C on its own showed superior protection against APAP-induced liver injury in rats compared to the other vitamins. The proliferation of APAP-intoxicated liver cells in vitro was highest when protected with the vitamins' combination.

A Functional Food Mixture "Protector" Reinforces the Protective Immune Parameters against Viral Flu Infection in Mice.

Background: Viral influenza infection causes serious health issues especially when an outbreak occurs. Although influenza virus vaccines are available and each year manufactures modify the vaccine depending on the expected mutated strain, it is still far from satisfactory, mainly in young children and older adults. Therefore, a product that can support and shape the immune system to protect against viral flu infections is highly essential. Methods: A functional food water-soluble mixture of pomegranate, red grape, dates, olive fruit, figs, and ginger extracts, termed herein “Protector”, was prepared and tested in stimulating/modulating the production of specific cytokines, and hemagglutinin inhibition (HAI) antibodies following viral flu vaccination in mice. Results: A single intraperitoneal or multiple oral administration for 1⁻7 days of “Protector” significantly increased the production of interferon (IFN)-γ and interleukin (IL)-12 in blood, spleen, and lungs of mice. When “Protector” was orally administered for one week following a single vaccine injection (primary immunization) or for two weeks (one week apart) following double vaccine injections (secondary immunization), mice significantly produced higher titers of HAI antibodies. This increase in HAI antibodies was associated with Pillow-inducing significant and different changes in vaccine-induced IFN-γ, IL-12, IL-6 and IL-22 following primary and secondary immunizations. Conclusions: “Protector” administration reinforces the protective immune parameters against viral flu infection. Therefore, after performing preclinical toxicology studies and ensuring its safety, “Protector” should be considered a potential product to be tested in clinical trials to conclude its efficacy in reducing the devastating effects of flu infection in humans and its outbreaks.

Glucosamine modulates propranolol pharmacokinetics via intestinal permeability in rats.

Propranolol (PROP) undergoes extensive first-pass metabolism by the liver resulting in a relatively low bioavailability (13-23%); thus, multiple oral doses are required to achieve therapeutic effect. Since some studies have reported that glucosamine (GlcN) can increase the bioavailability of some drugs, therefore, it is aimed to study whether GlcN can change the pharmacokinetic parameters of PROP, thus modulating its bioavailability. When PROP was orally co-administered with GlcN (200mg/kg) to rats, PROP area under curve (AUC) and maximum concentration (Cmax) were significantly decreased by 43% (p<0.01) and 33% (p<0.05), respectively. In line with the in vivo results, in silico simulations confirmed that GlcN decreased rat intestinal effective permeability (Peff) and increased PROP clearance by 50%. However, in situ single pass intestinal perfusion (SPIP) experiments showed that GlcN significantly increased PROP serum levels (p<0.05). Furthermore, GlcN decreased PROP disposition/distribution into cultured hepatocytes in concentration dependent manner. Such change in the interaction pattern between GlcN and PROP might be attributed to the environment of the physiological buffer used in the in vitro experiments (pH7.2) versus the oral administration and thus, enhanced PROP permeability. Nevertheless, such enhancement was not detected when everted gut sacks were incubated with both drugs at the same pH in vitro. In conclusion, GlcN decreased PROP serum levels in rats in a dose-dependent manner. Such interaction might be attributed to decreased intestinal permeability and enhanced clearance of PROP in the presence of GlcN. Further investigations are still warranted to explain the in vitro inhibitory action of GlcN on PROP hepatocytes disposition and the involvement of GlcN in the intestinal and hepatic metabolizing enzymes of PROP at different experimental conditions.

Eriobotrya japonica Water Extract Characterization: An Inducer of Interferon-Gamma Production Mainly by the JAK-STAT Pathway.

Eriobotrya japonica (Thunb.) Lindl. (Loquat) (EJ) has been used as a medicinal plant to treat chronic bronchitis, coughs, phlegm, high fever and gastro-enteric disorders. Since the traditional use of EJ is related to modulating inflammation processes, our earlier studies on EJ leaves were performed on the water extract to investigate specific cytokines' modulation. These earlier studies, however, have shown that EJ leaf water extract (WE) and the water phase (WP) induce cytokines' production in in vitro and in vivo models. Therefore, the aim of this study was to specify the group(s) of compounds in EJ leaves that have this immunomodulatory activity and their mechanism of action. WE was obtained from boiling the leaves followed by butanol extraction, yielding a butanol-water phase (WP). WP was then subjected to methanol:acetone fractionation, yielding upper (MAU) and lower (MAL) phases. For further fractionation, MAU was subjected to column chromatography followed by elution with ethanol:water (EW), methanol:ethanol (ME) and, lastly, acetone:water (AW), respectively, to reveal three sub-fractions; MAU-EW, MAU-ME and MAU-AW. MAU-AW significantly increased IFN-γ production from unstimulated and stimulated mouse spleen cells, as well as CD3+ T cells and natural killer cells. Furthermore, the fold increase of IFN-γ production by MAU-AW was concentration dependent, higher than the parent extract or any of the other sub-fractions, and such an IFN-γ increase was reversed by two JAK-STAT inhibitors. In addition, MALDI-TOF-MS analysis of the extracts and sub-fractions showed compounds with molecular weights of >500 Daltons. The MAU-AW sub-fraction contained more polar compounds, such as flavonol and caffeic glycosides. In conclusion, these polar compounds in the EJ extract are responsible for inducing IFN-γ production. Further chemical elucidation is warranted to lead to a specific IFN-γ inducer and an immunomodulator in polarizing immune cells and balancing immune responses in certain diseases.

Increased Salivary Nitric Oxide and G6PD Activity in Refugees with Anxiety and Stress.

Anxiety and stress are related to physiological changes in humans. Accumulating evidence suggests a cross-talk between psychiatric disorders and oxidative stress. The objective of this study was to compare oxidative stress and defensive antioxidant biomarkers in a group of refugees with acute anxiety and stress with a group of local Jordanians. The Hamilton Anxiety Rating Scale (HAM-A) and the Perceived Stress Scale (PSS) Arabic version were used to assess anxiety and stress respectively. Salivary nitric oxide concentration, glucose-6-phosphate dehydrogenase (G6PD) activity and total salivary protein were compared. As expected, refugees showed higher anxiety and stress scores compared with Jordanians. Also, we report a significant increase in salivary nitric oxide and G6PD activity in the refugee group while total protein concentration did not vary between the two groups. This is the first study that demonstrates an increase in nitric oxide and G6PD activity in the saliva of refugees, thus highlighting their potential role as possible biomarkers in anxiety and stress disorders. Copyright © 2015 John Wiley & Sons, Ltd.

Dichloroacetate modulates cytokines toward T helper 1 function via induction of the interleukin-12-interferon-γ pathway.

BACKGROUND: Dichloroacetate (DCA) is one of the new, promising anticancer drugs. DCA restores normal mitochondrial function and enables cancer cells to undergo apoptosis. In addition, DCA was found to modulate certain signaling pathways involving some transcription factors. The latter encouraged us to study DCA immunomodulatory activity on cytokines and their association with increasing DCA cancer cell cytotoxicity. METHODS AND RESULTS: Cell viability assay was used to determine the effect of different concentrations of DCA on the survival of 3-methylcholanthrene (MCA) fibrosarcoma cell line. DCA decreased the percent survival of MCA fibrosarcoma in a dose-dependent manner (P<0.01). Furthermore, this percent survival was further reduced when MCA fibrosarcoma cells were cocultured with mouse splenocytes. The latter was observed at 10 mM DCA (P<0.01), and the inhibitory concentration at 50% dropped from 23 mM to 15.6 mM DCA (P<0.05). In addition, DCA significantly enhanced interferon (IFN)-γ but not interleukin (IL)-17 production levels in unstimulated and stimulated mouse spleen cells. To investigate the mechanism of DCA on IFN-γ production, DCA cytokine modulatory effect was tested on unstimulated macrophages, T-cells, and natural killer cells. DCA significantly increased IL-12 production from macrophages but did not modulate the production of IFN-γ from either T-cells or natural killer cells. Moreover, the DCA-enhancing effect on IFN-γ production was reversed by anti-IL-12 antibody. Also, the DCA cytokine modulatory effect was tested in vivo after inducing mouse skin inflammation using phorbol 12-myristate 13-acetate (PMA). DCA restored PMA-lowered IFN-γ and IL-12 levels and normalized PMA-increased transforming growth factor-ß level, but it inhibited IL-10 levels even further (P<0.05). CONCLUSION: DCA has immunomodulatory activity, mainly via activation of the IL-12-IFN-γ pathway and is able to modulate cytokines toward T helper 1 lymphocyte function. These DCA immunomodulatory effects are promising and further investigations are required to develop protocols for its use in cancer treatment.