Isorhamnetin: A review of pharmacological effects

Isorhamnetin promotes functional recovery in rats with spinal cord injury by abating oxidative stress and modulating M2 macrophages/microglia polarization

Spinal cord injury (SCI), mostly caused by sports injuries, falls, or traffic accidents, is a major cause of disability. The aim of current work was to investigate the therapeutic effect of isorhamnetin (ISO) on functional recovery in rats with SCI. The male adult rats were exposed to a clip-compression SCI and treated with ISO. ISO treatment improved locomotor function and reduced the loss of motor neurons in SCI rats. Treatment with ISO markedly relieved SCI-induced hypersensitivities to mechanical and thermal stimulation in rats. ISO treatment activated nuclear factor-erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) pathway and abated oxidative stress in injured spinal cords. ISO treatment partly suppressed microglial and glial activation and reduced expression of inflammatory cytokines including TNF-α, monocyte chemotactic protein-1 (MCP-1), and IL-1β in injured spinal cords. More importantly, ISO treatment promoted M2 macrophage activation in the injured region. lipopolysaccharide (LPS) or IL-4 was employed to stimulate macrophages/microglia into M1 or M2 phenotype in cultured BV2 cells in vitro. ISO treatment enhanced the expression of characteristic microglial anti-inflammatory polarization markers in BV2 cells. In conclusions, ISO treatment promotes functional recovery in rats with SCI by abating oxidative stress and modulating M1/M2 macrophage polarization.

Bioactive and Nutritional Potential of Medicinal and Aromatic Plant (MAP) Seasoning Mixtures

Medicinal and aromatic plants (MAPs), worldwide appreciated and used as condiments, dyes, and preservatives, possess several biological properties that justify their continuous application in the food industry. In the present study, the nutritional and chemical profiles, as well as the bioactive properties of four combinations of condiments, sold for seasoning poultry, meat, fish, and salads, were evaluated. Twenty-five phenolic compounds (HPLC-DAD-ESI/MS) were identified, with apigenin-O-malonyl-pentoside-hexoside as the major compound detected in all extracts. Oxalic and citric acids were identified in all mixtures (UFLC-PDA), as well as all the four tocopherol isoforms (HPLC-fluorescence). Regarding bioactivities, the mixtures for meat and salads (TBARS) and meat and poultry (OxHLIA) stood out for their antioxidant potential, whereas for the anti-inflammatory and antitumor properties, the mixtures revealing the greatest results were those for poultry and salad, respectively. In terms of antimicrobial activity, all the mixtures revealed the capacity to inhibit the growth of some bacterial strains. In brief, condiment mixtures showed to be a good source of bioactive compounds, as they confer health benefits, validating the importance of their inclusion in the human diet as a good dietary practice.

Exploring the Oxidative Stress Mechanism of Buyang Huanwu Decoction in Intervention of Vascular Dementia Based on Systems Biology Strategy

OBJECTIVE

To explore the oxidative stress mechanism of modified Buyang Huanwu decoction (MBHD) in intervention of vascular dementia (VD) based on systems biology strategy.

METHODS

In this study, through the reverse virtual target prediction technology and transcriptomics integration strategy, the active ingredients and potential targets of MBHD treatment of VD were analyzed, and the drug-disease protein-protein interaction (PPI) network was constructed. Then, bioinformatics analysis methods are used for Gene Ontology (GO) enrichment analysis and pathway enrichment analysis, and finally find the core biological process. After that, in animal models, low-throughput technology is used to detect gene expression and protein expression of key molecular targets in oxidative stress-mediated inflammation and apoptosis signaling pathways to verify the mechanism of MBHD treatment of VD rats. Finally, the potential interaction relationship between MBHD and VD-related molecules is further explored through molecular docking technology.

RESULTS

There are a total of 54 MBHD components, 252 potential targets, and 360 VD genes. The results of GO enrichment analysis and pathway enrichment analysis showed that MBHD may regulate neuronal apoptosis, nitric oxide synthesis and metabolism, platelet activation, NF-κB signaling pathway-mediated inflammation, oxidative stress, angiogenesis, etc. Among them, SIRT1, NF-κB, BAX, BCL-2, CASP3, and APP may be important targets for MBHD to treat VD. Low-throughput technology (qRT-PCR/WB/immunohistochemical technology) detects oxidative stress-mediated inflammation and apoptosis-related signaling pathway molecules. The molecular docking results showed that 64474-51-7, cycloartenol, ferulic acid, formononetin, kaempferol, liquiritigenin, senkyunone, wallichilide, xanthinin, and other molecules can directly interact with NF-κB p65, BAX, BCL-2, and CASP3.

CONCLUSION

The active compounds of MBHD interact with multiple targets and multiple pathways in a synergistic manner, and have important therapeutic effects on VD mainly by balancing oxidative stress/anti-inflammatory and antiapoptotic, enhancing metabolism, and enhancing the immune system.

New insight into the role of isorhamnetin as a regulator of insulin signaling pathway in type 2 diabetes mellitus rat model: Molecular and computational approach

We intended to examine the molecular mechanism of action of isorhamnetin (IHN) to regulate the pathway of insulin signaling. Molecular analysis, immunofluorescence, and histopathological examination were used to assess the anti-hyperglycemic and insulin resistance lowering effects of IHN in streptozotocin /high fat diet-induced type 2 diabetes using Wistar rats. At the microscopic level, treatment with IHN resulted in the restoration of myofibrils uniform arrangement and adipose tissue normal architecture. At the molecular level, treatment with IHN at three different doses showed a significant decrease in m-TOR, IGF1-R & LncRNA-RP11-773H22.4. expression and it up-regulated the expression of AKT2 mRNA, miR-1, and miR-3163 in both skeletal muscle and adipose tissue. At the protein level, IHN treated group showed a discrete spread with a moderate faint expression of m-TOR in skeletal muscles as well as adipose tissues. We concluded that IHN could be used in the in ameliorating insulin resistance associated with type 2 diabetes mellitus.

Isorhamnetin Ameliorates Aspergillus fumigatus Keratitis by Reducing Fungal Load, Inhibiting Pattern-Recognition Receptors and Inflammatory Cytokines

Purpose

Isorhamnetin is a natural flavonoid with both antimicrobial and anti-inflammatory properties, but its effect on fungal keratitis (FK) remains unknown. The current study aims to investigate the antifungal and anti-inflammatory effects of isorhamnetin against mouse Aspergillus fumigatus keratitis.

Methods

In vitro, the lowest effective concentration of isorhamnetin was assessed by minimum inhibitory concentration and cytotoxicity tests in human corneal epithelial cells (HCECs) and RAW264.7 cells. The antifungal property was investigated by scanning electron microscopy and propidium iodide uptake test. The anti-inflammatory effect of isorhamnetin in HCECs and RAW264.7 cells was observed by quantitative real-time polymerase chain reaction (qRT-PCR). In the eyes of mice with A. fumigatus keratitis, FK severity was evaluated using clinical score, plate counting, histological staining and periodic acid Schiff staining. In vivo, the anti-inflammatory effect of isorhamnetin was examined by immunofluorescence staining, myeloperoxidase assay, Western blot, enzyme-linked immunosorbent assay, and qRT-PCR.

Results

In HCECs and RAW264.7 cells, isorhamnetin significantly inhibited A. fumigatus conidia growth and hyphae viability at 80 µg/mL without affecting cell viability. In vitro, isorhamnetin altered A. fumigatus hyphal morphology and membrane integrity. In A. fumigatus keratitis mouse model, isorhamnetin treatment alleviated the severity of FK by reducing corneal fungal load and inhibiting neutrophil recruitment. In addition, the mRNA and protein expression levels of TLR-2, TLR-4, Dectin-1, IL-1β, and tumor necrosis factor-α were significantly decreased in isorhamnetin-treated groups in vivo and in vitro.

Conclusions

Isorhamnetin improves the prognosis of A. fumigatus keratitis in mice by inhibiting the growth of A. fumigatus, reducing the recruitment of neutrophils and downregulating inflammatory factors.

Flavonols as potential antiviral drugs targeting SARS-CoV-2 proteases (3CLpro and PLpro), spike protein, RNA-dependent RNA polymerase (RdRp) and angiotensin-converting enzyme II receptor (ACE2)

The novel coronavirus outbreak (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents the actual greatest global public health crisis. The lack of efficacious drugs and vaccines against this viral infection created a challenge for scientific researchers in order to find effective solutions. One of the promising therapeutic approaches is the search for bioactive molecules with few side effects that display antiviral properties in natural sources like medicinal plants and vegetables. Several computational and experimental studies indicated that flavonoids especially flavonols and their derivatives constitute effective viral enzyme inhibitors and possess interesting antiviral activities. In this context, the present study reviews the efficacy of many dietary flavonols as potential antiviral drugs targeting the SARS-CoV-2 enzymes and proteins including Chymotrypsin-Like Protease (3CLpro), Papain Like protease (PLpro), Spike protein (S protein) and RNA-dependent RNA polymerase (RdRp), and also their ability to interact with the angiotensin-converting enzyme II (ACE2) receptor. The relationship between flavonol structures and their SARS-CoV-2 antiviral effects were discussed. On the other hand, the immunomodulatory, the anti-inflammatory and the antiviral effects of secondary metabolites from this class of flavonoids were reported. Also, their bioavailability limitations and toxicity were predicted.

Artemisia scoparia and Metabolic Health: Untapped Potential of an Ancient Remedy for Modern Use

Botanicals have a long history of medicinal use for a multitude of ailments, and many modern pharmaceuticals were originally isolated from plants or derived from phytochemicals. Among these, artemisinin, first isolated from Artemisia annua, is the foundation for standard anti-malarial therapies. Plants of the genus Artemisia are among the most common herbal remedies across Asia and Central Europe. The species Artemisia scoparia (SCOPA) is widely used in traditional folk medicine for various liver diseases and inflammatory conditions, as well as for infections, fever, pain, cancer, and diabetes. Modern in vivo and in vitro studies have now investigated SCOPA's effects on these pathologies and its ability to mitigate hepatotoxicity, oxidative stress, obesity, diabetes, and other disease states. This review focuses on the effects of SCOPA that are particularly relevant to metabolic health. Indeed, in recent years, an ethanolic extract of SCOPA has been shown to enhance differentiation of cultured adipocytes and to share some properties of thiazolidinediones (TZDs), a class of insulin-sensitizing agonists of the adipogenic transcription factor PPARγ. In a mouse model of diet-induced obesity, SCOPA diet supplementation lowered fasting insulin and glucose levels, while inducing metabolically favorable changes in adipose tissue and liver. These observations are consistent with many lines of evidence from various tissues and cell types known to contribute to metabolic homeostasis, including immune cells, hepatocytes, and pancreatic beta-cells. Compounds belonging to several classes of phytochemicals have been implicated in these effects, and we provide an overview of these bioactives. The ongoing global epidemics of obesity and metabolic disease clearly require novel therapeutic approaches. While the mechanisms involved in SCOPA's effects on metabolic, anti-inflammatory, and oxidative stress pathways are not fully characterized, current data support further investigation of this plant and its bioactives as potential therapeutic agents in obesity-related metabolic dysfunction and many other conditions.

Flavonoids in the Treatment of Diabetes: Clinical Outcomes and Mechanism to Ameliorate Blood Glucose Levels

BACKGROUND

For thousands of years, natural food products have been used as a medicine for treating diseases that affect the human body, including diabetes mellitus (DM). Lately, several investigations have been performed on the flavonoid derivatives of plant origin, and their biological activity has been extensively studied.

METHODS

Given our need to know more mechanisms for treating DM, we performed a thorough research review on treating diabetes mellitus based on flavonoids, their therapeutic potential, and biological action.

RESULTS

Flavonoids reduce complications in addition to their vital role as effective supplements for preventing diabetes mellitus by regulating glucose metabolism, lipid profile, liver enzyme activity, a protein kinase inhibitor, PPAR, and AMPK with NF-κB.

CONCLUSION

The articles that we reviewed showed the positive role of flavonoids, which in a certain way reduce diabetes, but their side effects still need to be studied further.This review is focused on describing the different types of dietary flavonoids along with their mechanisms of reducing blood glucose and enhancing insulin sensitivity, as well as their side effects.

Rea regulates microglial polarization and attenuates neuronal apoptosis via inhibition of the NF-κB and MAPK signalings for spinal cord injury repair

Inflammation and neuronal apoptosis aggravate the secondary damage after spinal cord injury (SCI). Rehmannioside A (Rea) is a bioactive herbal extract isolated from Rehmanniae radix with low toxicity and neuroprotection effects. Rea treatment inhibited the release of pro-inflammatory mediators from microglial cells, and promoted M2 polarization in vitro, which in turn protected the co-cultured neurons from apoptosis via suppression of the NF-κB and MAPK signalling pathways. Furthermore, daily intraperitoneal injections of 80 mg/kg Rea into a rat model of SCI significantly improved the behavioural and histological indices, promoted M2 microglial polarization, alleviated neuronal apoptosis, and increased motor function recovery. Therefore, Rea is a promising therapeutic option for SCI and should be clinically explored.

Fabrication of Nanosuspensions to Improve the Oral Bioavailability of Total Flavones from Hippophae rhamnoides L. and their Comparison with an Inclusion Complex

The aim of this work was to increase the solubility and oral bioavailability of isorhamnetin, kaempferol, and quercetin in the total flavones of Hippophae rhamnoides L. (TFH) by preparing their nanosuspensions (NSs) and an inclusion complex. Based on the particle size and zeta potential, P407, Soluplus, SDS, PEG-6000, and HP-β-CD were selected as stabilizers. TFH NSs and a TFH/HP-β-CD inclusion complex were prepared, and their morphology, crystallinity, molecular interactions, and cytotoxicity were investigated. Furthermore, the saturation solubility, dissolution, and pharmacokinetics of the three flavonoids in the TFH, TFH NSs, and TFH/HP-β-CD inclusion complex were compared. The five obtained TFH NSs were physically stable, and their particle sizes were all below 200 nm. The solubility and dissolution of the three active components were obviously enhanced by the formation of the TFH NSs and TFH/HP-β-CD inclusion complex. Correspondingly, the oral bioavailability of isorhamnetin, kaempferol, and quercetin increased up to 4.11-, 3.85-, and 6.73-fold, respectively, in the TFH NSs and 2.89-, 3.71-, and 9.51-fold, respectively, in the TFH/HP-β-CD inclusion complexes compared to those in the raw TFH. In brief, both NSs and inclusion complexes can improve the oral bioavailability of the three flavonoids in TFH. Taking the drug loading and the stable ratio of the multiple components into consideration, the NSs is a more promising strategy than the inclusion complex for increasing the oral bioavailability of multiple water-insoluble components in herbal extracts. Graphical abstract.