Neurological disorders, such as amyotrophic lateral sclerosis, Parkinson’s disease, and Alzheimer’s disease, are commonly associated with persistent neuro-inflammation, and there is an urgent need to discover new therapeutic agents that may target the various pathways involved in neurodegeneration. In this study, we investigated the therapeutic potential of folecitin, a flavonoid isolated from Hypericum oblongifolium, against lipopolysaccharide (LPS)-induced oxidative stress associated with neurodegeneration, amyloidogenic Aβ production pathway, and memory dysfunction in mice. LPS was administered i.p. at 250 µg/kg/day for 3 weeks, followed by the administration of folecitin at a dose of 30 mg/kg/day for the last two weeks. A Western blot technique was used to assess the expression of different proteins involved in oxidative stress, neurodegeneration, and neuronal synapse. Results indicated that folecitin significantly reduced LPS-induced apoptotic neurodegeneration, including the expression of BAX, Caspase-3, and PARP-1 proteins, inhibited BACE1, and the amyloidogenic Aβ production pathway. Folecitin improved both pre- and post-neuronal synapse, as well as memory dysfunction. Furthermore, folecitin significantly activated endogenous antioxidant proteins such as Nrf-2 and HO-1 via stimulating the phosphorylation of Akt proteins. These findings suggest that folecitin may be a suitable lead to design new drugs for neurotoxin-triggered neurodegenerative disorders.

bZIP transcription factors, basic leucine zipper, play significant roles in plants’ growth and development processes, as well as in response to biological and abiotic stress. Hypericum perforatum is one of the world's top three best-selling herbal medicines, mainly used to treat depression. However, there is no systematic identification or functional analysis of the bZIP gene family in H. perforatum. In this study, 79 HpbZIP genes were identified. Based on phylogenetic analysis, the HpbZIP gene family was divided into ten groups, designated A-I, and S. The physicochemical properties, gene structures, protein conserved motifs, and Gene Ontology enrichments of all HpbZIPs were systematically analyzed. The expression patterns of all genes in different tissues of H. perforatum (root, stem, leaf, and flower) were analyzed by qRT-PCR, revealing the different expression patterns of HpbZIP under abiotic stresses. HpbZIP69 protein is localized in the nucleus. According to the results of the yeast one-hybrid (Y1H) assays, HpbZIP69 can bind to the HpASMT2 (N-Acetylserotonin O-methyltransferase) gene promoter ( G-box cis-element ) to activate its activity. Overexpressing HpbZIP69 transgenic Arabidopsis lines enhanced tolerance to drought. The content of MDA and H2O2 content was significantly decreased, and the activity of superoxide dismutase (SOD) was considerably increased under the drought stress. These results may aid in additional functional studies of HpbZIP transcription factors and cultivating drought-resistant medicinal plants.

The aim of this study was to investigate in-vitro antioxidant properties and in-vivo protective effects of different concentrations of Hypericum triquetrifolium Turra. (HT) seed methanol extracts against acute hepatotoxicity, myelotoxicity and hematotoxicity in rats exposed to overdose of cyclophosphamide (CP). HT seed methanol extracts were tested in view of its in-vitro antioxidant activities as total phenolic contents and DPPH free radical-scavenging activity. To investigate in-vivo protective effects of HT seed methanol extracts on rat tissues; tested animals were divided into nine groups. Three groups only were treated with HT extracts (25, 50 and 100 mg/kg HT) for 6 days. Three groups were pre-treated with the extract of HT (25, 50 and 100 mg/kg HT) for 6 days and on the last day they were injected with single dose of CP (150-mg/kg body weight). Two groups were used as control groups and one group was only treated with CP (150 mg/kg) on the 6th day. The toxic effects of CP and protective effects of HT extracts on the nucleated cells which were produced by bone marrow and serum alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), oxidative stress index (OSI) levels were investigated biochemically. Additionally, liver tissue samples were examined histopathologically. Our results show that HT seed methanol extract has high total phenolic content and antioxidant activity. Over dose CP administration caused hepatotoxicity, myelotoxicity and hematotoxicity on rat. Whereas, 25, 50 and 100 mg/kg HT plus CP administered groups showed significant protective effects on nucleated cells. And 25, 50, 100 mg/kg HT plus CP treated groups showed an important decrease on serum ALT, ALP, LDH and OSI levels when compared with CP treated group. Our results showed that the administration of different HT doses with high doses of CP significantly reduced hepatotoxicity, myelotoxicity and hematoxicity on rats.

Fifteen transgenic shoot clones (TS A-TS O) regenerated from Hypericum perforatum hairy roots were evaluated for growth characteristics, phenylpropanoid, and naphthodianthrone production, as well as non-enzymatic and enzymatic antioxidant status. Transgenic shoots displayed higher biomass production and non-altered phenotype compared to control shoots. Phenylpropanoid production in TS was not related to phenylalanine ammonia lyase activity indicating that alternative enzymes could be involved in the regulation of phenylpropanoid/flavonoid biosynthesis. The positive correlation between phenylpropanoids (phenolic acids, flavonoids, flavan-3-ols, tannins) and non-enzymatic antioxidant assays suggested that these compounds are the main contributors to the redox state and radical scavenging properties of TS clones. More importantly, enhanced naphthodianthrone production (hypericin, pseudohypericin and protopseudohypericin) in TS was associated with the number of leaf dark glands. Concerning the enzymatic antioxidant status of TS, guaiacol peroxidase was shown as the main enzyme that turn down H2O2 levels, while the up-regulation of superoxide dismutase coincided with decreased O2•− production. The efficiency of antioxidant enzymes for O2•− and H2O2 neutralization declined the MDA level and consequently delayed lipid peroxidation in TS clones. Altogether, H. perforatum transgenic shoots could be proposed as a prospective biotechnological system for scale-up production of naphthodianthrones and phenylpropanoids with antioxidant properties.