Passiflora actinia hydroalcoholic extract and its major constituent, isovitexin, are neuroprotective against glutamate-induced cell damage in mice hippocampal slices

Phytochemistry, nutritional composition, health benefits and future prospects of Passiflora: A review

Passiflora, also known as "passion fruit", is widely grown in tropical and subtropical regions. It is not only eaten raw but is also widely used in processed foods. Various extracts, juices and isolated compounds show a wide range of health effects and biological activities, such as antioxidant, anti-inflammatory, sedative, and neuroprotective effects. In this review, we not only review the phytochemical properties of Passiflora but also highlight the potential of Passiflora for food applications and the use of all parts as a source of ingredients for medicines and cosmetics that promote health and well-being. This will provide theoretical support for the integrated use of such natural products.

The effect of isovitexin on lipopolysaccharide-induced renal injury and inflammation by induction of protective autophagy

Chronic kidney disease (CKD) is a systemic inflammatory syndrome that includes tubulointerstitial inflammation. Lipopolysaccharide (LPS), the outer membrane of Gram-negative bacteria, can increase reactive oxygen species production (ROS) that triggers cell inflammation. Isovitexin (IV) is a flavone that has the potential for anticancer, antioxidant, and anti-inflammatory. This study aimed to hypothesize that IV inhibited LPS-induced renal injury in vitro and in vivo. In vitro study, IV prevented LPS-induced ROS production and increased cell viability on SV40-MES-13 cells. Additionally, IV ameliorated mitochondrial membrane potential, downregulated inflammation and pyroptosis factors on LPS treatment. We found that LPS treatment reduced the expression of autophagy, however, this effect was reversed by IV. In vivo study, the renal injury model in C57BL/6 mice cotreatment with IV was examined. In addition, IV decreased LPS-induced glomerular atrophy and reduced inflammation-related cytokines releases. Further showed that IV could significantly reduce LPS-induced inflammation and pyroptosis factors in mice. Under the immunostaining, increased fluorescence of LC3 autophagy-related protein was recovered by IV. In summary, IV ameliorated renal injury, inflammation and increased protected autophagy by anti-ROS production, anti-inflammation, and anti-pyroptosis. In the future, the safety of isovitexin as a novel perspective for CKD patients should be evaluated in further clinical studies.

Neuroprotective and Anti-Neuroinflammatory Properties of Vignae Radiatae Semen in Neuronal HT22 and Microglial BV2 Cell Lines

The important factors in the pathogenesis of neurodegenerative disorders include oxidative stress and neuron-glia system inflammation. Vignae Radiatae Semen (VRS) exhibits antihypertensive, anticancer, anti-melanogenesis, hepatoprotective, and immunomodulatory properties. However, the neuroprotective effects and anti-neuroinflammatory activities of VRS ethanol extract (VRSE) remained unknown. Thus, this study aimed to investigate the neuroprotective and anti-inflammatory activities of VRSE against hydrogen peroxide (H₂O₂)-induced neuronal cell death in mouse hippocampal HT22 cells and lipopolysaccharide (LPS)-stimulated BV2 microglial activation, respectively. This study revealed that VRSE pretreatment had significantly prevented H₂O₂-induced neuronal cell death and attenuated reactive oxygen species generations in HT22 cells. Additionally, VRSE attenuated the apoptosis protein expression while increasing the anti-apoptotic protein expression. Further, VRSE showed significant inhibitory effects on LPS-induced pro-inflammatory cytokines in BV2 microglia. Moreover, VRSE pretreatment significantly activated the tropomyosin-related kinase receptor B/cAMP response element-binding protein, brain-derived neurotrophic factor and nuclear factor erythroid 2-related factor 2, and heme oxygenase-1 signaling pathways in HT22 cells exposed to H₂O₂ and inhibited the activation of the mitogen-activated protein kinase and nuclear factor-κB mechanism in BV2 cells stimulated with LPS. Therefore, VRSE exerts therapeutic potential against neurodegenerative diseases related to oxidative stress and pathological inflammatory responses.

P. edulis Extract Protects Against Amyloid-β Toxicity in Alzheimer's Disease Models Through Maintenance of Mitochondrial Homeostasis via the FOXO3/DAF-16 Pathway

Alzheimer's disease (AD) is a common and devastating disease characterized by pathological aggregations of beta-amyloid (Aβ) plaques extracellularly, and Tau tangles intracellularly. While our understandings of the aetiologies of AD have greatly expanded over the decades, there is no drug available to stop disease progression. Here, we demonstrate the potential of Passiflora edulis (P. edulis) pericarp extract in protecting against Aβ-mediated neurotoxicity in mammalian cells and Caenorhabditis elegans (C. elegans) models of AD. We show P. edulis pericarp protects against memory deficit and neuronal loss, and promotes longevity in the Aβ model of AD via stimulation of mitophagy, a selective cellular clearance of damaged and dysfunctional mitochondria. P. edulis pericarp also restores memory and increases neuronal resilience in a C. elegans Tau model of AD. While defective mitophagy-induced accumulation of damaged mitochondria contributes to AD progression, P. edulis pericarp improves mitochondrial quality and homeostasis through BNIP3/DCT1-dependent mitophagy and SOD-3-dependent mitochondrial resilience, both via increased nuclear translocation of the upstream transcriptional regulator FOXO3/DAF-16. Further studies to identify active molecules in P. edulis pericarp that could maintain neuronal mitochondrial homeostasis may enable the development of potential drug candidates for AD.

Multitargeted Effects of Vitexin and Isovitexin on Diabetes Mellitus and Its Complications

BACKGROUND

Till date, there is no known antidote to cure diabetes mellitus despite the discovery and development of diverse pharmacotherapeutic agents many years ago. Technological advancement in natural product chemistry has led to the isolation of analogs of vitexin and isovitexin found in diverse bioresources. These compounds have been extensively studied to explore their pharmacological relevance in diabetes mellitus. Aim of the Study. The present review was to compile results from in vitro and in vivo studies performed with vitexin and isovitexin derivatives relating to diabetes mellitus and its complications. A systematic online literature query was executed to collect all relevant articles published up to March 2020.

RESULTS

In this piece, we have collected data and presented it in a one-stop document to support the multitargeted mechanistic actions of vitexin and isovitexin in controlling diabetes mellitus and its complications.

CONCLUSION

Data collected hint that vitexin and isovitexin work by targeting diverse pathophysiological and metabolic pathways and molecular drug points involved in the clinical manifestations of diabetes mellitus. This is expected to provide a deeper understanding of its actions and also serve as a catapult for clinical trials and application research.

Isovitexin modulates autophagy in Alzheimer's disease via miR-107 signalling

Background:

Alzheimer’s disease (AD) is an ultimately fatal, degenerative brain disease in the elderly people. In the current work, we assessed the defensive capability of isovitexin (IVX) through an intracerebroventricular injection of streptozotocin (STZ)-induced AD mouse model.

Methods:

Mice were separated into four cohorts: sham-operated control mice; STZ-intoxicated Alzheimer’s mice; IVX cohort, IVX + STZ; and Ant-107 cohort, antagomiR-107 + IVX/STZ as in the IVX cohort.

Results:

The outcomes indicated that IVX administration ameliorated spatial memory loss and blunted a cascade of neuro-noxious episodes – including increased amyloid-beta (Aβ) and degraded myelin basic protein burden, neuroinflammation (represented by elevated caspase-1, TNF-α and IL-6 levels) and autophagic dysfunction (represented by altered LC3-II, Atg7 and beclin-1 expressions) – via the inhibition of PI3K/Akt/mTOR signalling axis. We considered the question of whether the epigenetic role of microRNA-107 (miR-107) has any impact on these events, by using antagomiR-107.

Conclusion:

This probing underscored that miR-107 could be a pivotal regulatory button in the activation of molecular signals linked with the beneficial autophagic process and anti-inflammatory activities in relation to IVX treatment. Hence, this report exemplifies that IVX could guard against Aβ toxicity and serve as an effectual treatment for patients afflicted with AD.

Isovitexin Suppresses Cancer Stemness Property And Induces Apoptosis Of Osteosarcoma Cells By Disruption Of The DNMT1/miR-34a/Bcl-2 Axis

BACKGROUND

Isovitexin (apigenin-6-C-glucoside, ISOV) is a natural flavonoid that exhibits tumor suppressive activity on various types of cancer. However, it is unknown whether the mechanism of its action in osteosarcoma (OS) is associated with epigenetic regulation and whether it involves DNA methyltransferase 1 (DNMT1), microRNAs and their targets.

MATERIALS AND METHODS

The present study investigated the effects of ISOV on DNMT1 activation and miR-34a and Bcl-2 expression levels in order to explain the mechanism underlying ISOV-mediated repression of proliferation and stemness. In addition, the induction of apoptosis in the spheres derived from OS cells was investigated.

RESULTS

The results indicated that ISOV significantly repressed survival, induced apoptosis and decreased the level of CD133, CD44, ABCG2 and ALDH1 mRNA in the spheres derived from U2OS (U2OS-SC) and MG63 cells (MG63-SC). ISOV further reduced the sphere formation rate of U2OS-SC and MG63-SC. It is important to noted that, ISOV inhibited tumor growth and reduced tumor size of U2OS-SC xenografts in nude mice, which was accompanied by decreased CD133 protein levels, elevated apoptotic index, downregulation of proliferating cell nuclear antigen (PCNA) expression, reduced DNMT1 activity and expression, increased miR-34a and decreased Bcl-2 levels. We identified that Bcl-2 as a direct functional target of miR-34a. Furthermore, ISOV exhibited a synergistic effect with 5-aza-2'-deoxycytidine, the miR-34a mimic or ABT-263 in order to repress cell survival, induce apoptosis, downregulate CD133, CD44, ABCG2 and ALDH1 mRNA expression levels and reduce sphere formation rates of U2OS-SC and MG63-SC cells.

CONCLUSION

The findings suggested that ISOV-mediated epigenetic regulation involved the DNMT1/miR-34a/Bcl-2 axis and caused the suppression of stemness and induction of apoptosis in the spheres derived from OS cells. The data indicated that ISOV exhibited a novel efficient potential for the treatment of OS.

Isovitexin alleviates liver injury induced by lipopolysaccharide/d-galactosamine by activating Nrf2 and inhibiting NF-κB activation

The aim of this study was to investigate the protective effects and mechanism of isovitexin, a glycosylflavonoid isolated from rice hulls of Oryza sativa, on Lipopolysaccharide (LPS)/d-galactosamine (D-Gal)-induced acute liver injury. The mice were randomly divided into five groups: control group, LPS/D-Gal group, and LPS/D-Gal + isovitexin groups. The mice of LPS/D-Gal group were received of LPS (50 μg/kg) and D-gal (800 mg/kg) intraperitoneal. The mice of LPS/D-Gal + isovitexin groups were received isovitexin (25, 50, 100 mg/kg) 1 h before LPS/D-Gal treatment. The results showed that the severity of liver injury was attenuated by treatment of isovitexin, as confirmed by the decreased liver histopathologic changes, as well as serum AST and ALT levels. Furthermore, the levels of TNF-α in serum and liver tissues, MPO activity and MDA content were significantly inhibited by isovitexin. In addition, isovitexin significantly attenuated NF-κB phosphorylation induced by LPS/D-Gal. The expression of Nrf2 and HO-1 were significantly up-regulated by isovitexin. In conclusion, isovitexin could protect against LPS/D-Gal-induced liver injury by inhibiting inflammatory and oxidative responses. Isovitexin also had protective effects against carbon tetrachloride (CCl₄)-induced liver injury. Isovitexin may used as a potential agent for the treatment of liver injury.