Mangiferin exerts neuroprotective activity against lead-induced toxicity and oxidative stress via Nrf2 pathway.

Objective: The study was designed to assess the beneficial role of mangiferin (MGN) in lead (Pb)-induced neurological damages in the activation of Nrf2-governed enzymes, genes and proteins. Methods: A total of 96 weaned Wistar rats (48 males and 48 females, 26- to 27-day-old), weighing 50-80 g were used. The experiment was performed in six groups: normal group (control, n = 16), model group (chronic Pb exposed, n = 16), Dimercaptosuccinic acid (DMSA)-treated group (positive control, Pb + DMSA, n = 16), three MGN-treated groups with different doses (Pb + MGN, n = 48). Normal group freely had access to purified water. DMSA-treated group was given DMSA, which was clinically used as the standard treatment for moderate Pb poisoning, at 50 mg/kg (2 mL suspension with purified water) by intragastric gavage (ig) 4 continual days a week for 4 weeks, MGN-treated groups were given MGN at 50, 100, or 200 mg/kg (2 mL suspension with purified water) by ig daily for 4 weeks. At the end of the treatment, all rats were sacrificed and the brain samples were collected. The haematoxylin and eosin (H&E) staining was used for observation of histopathology. Commercial kit, real-time quantitative polymerase chain reaction (RT-qPCR), Western-blot and immunohistochemistry (IHC) detection were used to detect the mRNA and protein expression. Results: Eight weeks exposure to Pb-containing water resulted in pathological alterations, anti-oxidative system disorder in the brain, all of which were blocked by MGN in a Nrf2-dependent manner. Nrf2 downstream enzymes such as HO-1, NQO1, γ-GCS were activated. Nrf2, GCLC, GCLM, HO-1 mRNA and total Nrf2, Nuclear Nrf2, γ-GCS, HO-1 protein expression were affected too. Conclusion: MGN ameliorated morphological damage in the hippocampus. Its neuroprotective effects were achieved by the activation of the Nrf2 downstream genes. The data from this in vitro study indicates that MGN targeting Nrf2 activation is a feasible approach to reduce adverse health effects associated with Pb exposure. Thus, MGN could be an effective candidate agent for the Pb-induced oxidative stress and neurotoxicity in the human body.

Mangiferin attenuates TH1/TH2 cytokine imbalance in an ovalbumin-induced asthmatic mouse model.

Mangiferin is a major bioactive ingredient in Mangifera indica Linn. (Anacardiaceae) leaves. Aqueous extract of such leaves have been used as an indigenous remedy for respiratory diseases like asthma and coughing in traditional Chinese medicine. However, underlying molecular mechanisms of mangiferin on anti-asthma remain unclear. In our present study, we investigated the anti-asthmatic effect of mangiferin on Th1/Th2 cytokine profiles and explored its underlying immunoregulatory mechanism in mouse model of allergic asthma. Mangiferin significantly reduced the total inflammatory cell counts and eosinophil infiltration, decreased the production of ovalbumin-specific IgE in serum and PGD2 in BALF. The antibody array analysis showed that mangiferin down-regulated the levels of one group of cytokines/chemokines including Th2-related IL-4, IL-5, IL-13, and others IL-3, IL-9, IL-17, RANTES, TNF-α, but simultaneously up-regulated Th1-related IFN-γ, IL-2 and IL-10 and IL-12 expression in serum. Thus it attenuates the imbalance of Th1/Th2 cells ratio by diminishing the abnormal mRNA levels of Th1 cytokines (IFN-γ and IL-12) and Th2 cytokines (IL-4, IL-5 and IL-13). Finally, mangiferin substantially inhibited the activation and expression of STAT-6 and GATA-3 in excised lung tissues. Our results suggest that mangiferin can exert anti-asthmatic effect. The underlying mechanism may attribute to the modulation of Th1/Th2 cytokine imbalance via inhibiting the STAT6 signaling pathway.

Observation of non-odd order harmonics by sub-2-cycle laser pulses.

High order harmonics generation from argon gas was comprehensively investigated by using multi-cycle and few-cycle laser pulses. Non-odd order harmonics were observed for sub-5-fs pulses, compare to the normal odd-order harmonics in the multi-cycle case. Theoretic analysis shows that the new spectral structure origins from the asymmetry of laser field in few-cycle pulses. This asymmetry induced both amplitude and phase difference between attosecond pulses from consecutive half-cycle of the laser field, which change the interference property of attosecond pulses and result in complex spectrum.

[In vitro effect of Huyinling extract on Trichomonas tenax].

The active ingredient of Huyinling, a combination of Chinese traditional medicine, was extracted by five different ethanol concentrations (40%-80%). There were seven groups named as five Huyinling ethanol extract groups (40%, 50%, 60%, 70%, and 80%), metronidazole group and blank control. Each Huyinling ethanol extract group was further divided into five subgroups with final concentration of 6.25, 12.5, 25, 50, and 100 mg/ml, respectively. Metronidazole group was given 10 microg/ml of the drug. Each group had 4 wells with 125 microl T. tenax(2 x 10(5)/ml). At 12 h, 24 h and 48 h after drug treatment, the anti-T. tenax effect of Huyinling ethanol extract was tested by microscope counting method. At 24 h the effect of Huyinling on T. tenax was examined with methyl thiazolyl tetrazolium (MTl) assay. The results showed that the higher concentration of Huyinling ethanol extract, the better effect on anti-T. tenax. 60% Huyinling ethanol extract group with concentrations of 6.25 mg/ml and 12.5 mg/ml showed higher anti-T. tenax effect than other groups (P < 0.01). The ethanol extract of Huyinling granules has a remarkable effect on T. tenax, and among the groups, 60% ethanol extract shows the best anti-T. tenax activity.