Dendropanax morbifera Léveille extract ameliorates cesium-induced inflammation in the kidney and decreases antioxidant enzyme levels in the hippocampus

Dendropanax Morbiferus and Other Species from the Genus Dendropanax: Therapeutic Potential of Its Traditional Uses, Phytochemistry, and Pharmacology

The Dendropanax genus is a kind of flowering plant in the family of Araliaceae that encompasses approximately 91 to 95 species. Several Dendropanax species are used as traditional medicinal plants, extensively used Korea and South America and other parts of the world. Almost every part of the plant, including the leaves, bark, roots, and stems, can be used as traditional medicine for the prevention and management of a broad spectrum of health disorders. This paper sought to summarizes the ethnopharmacological benefits, biological activities, and phytochemical investigations of plants from the genus Dendropanax, and perhaps to subsequently elucidate potential new perspectives for future pharmacological research to consider. Modern scientific literature suggests that plants of the Dendropanax genus, together with active compounds isolated from it, possess a wide range of therapeutic and pharmacological applications, including antifungal, anti-complement, antioxidant, antibacterial, insect antifeedant, cytotoxic, anti-inflammatory, neuroprotective, anti-diabetic, anti-cancer, and anti-hypouricemic properties. The botanical descriptions of approximately six to 10 species are provided by different scientific web sources. However, only six species, namely, D. morbiferus, D. gonatopodus, D. dentiger, D. capillaris, D. chevalieri, and D. arboreus, were included in the present investigation to undergo phytochemical evaluation, due to the unavailability of data for the remaining species. Among these plant species, a high concentration of variable bioactive ingredients was identified. In particular, D. morbifera is a traditional medicinal plant used for the multiple treatment purposes and management of several human diseases or health conditions. Previous experimental evidence supports that the D. morbifera species could be used to treat various inflammatory disorders, diarrhea, diabetes, cancer, and some microbial infections. It has recently been reported, by our group and other researchers, that D. morbifera possesses a neuroprotective and memory-enhancing agent. A total of 259 compounds have been identified among six species, with 78 sourced from five of these species reported to be bioactive. However, there is no up-to-date information concerning the D. morbifera, its different biological properties, or its prospective benefits in the enhancement of human health. In the present study, we set out to conduct a comprehensive analysis of the botany, traditional medicinal history, and medicinal resources of species of the Dendropanax genus. In addition, we explore several phytochemical constituents identified in different species of the Dendropanax genus and their biological properties. Finally, we offer comprehensive analysis findings of the phytochemistry, medicinal uses, pharmacological actions, and a toxicity and safety evaluation of the D. morbifera species and its main bioactive ingredients for future consideration.

Neuroprotective effects of Dendropanax morbifera leaves on glutamate-induced oxidative cell death in HT22 mouse hippocampal neuronal cells

ETHNOPHARMACOLOGICAL RELEVANCE

Dendropanax morbifera (DM) has long been used as a traditional herbal medicine for migraines. Glutamate toxicity and oxidative stress have emerged as the possible triggers implicated in migraine pathogenesis.

AIM OF THE STUDY

We aimed to examine the neuroprotective effects of DM leaves (DML) on glutamate-induced oxidative cell death in HT22 mouse hippocampal neuronal cells.

MATERIALS AND METHODS

Molecular authentication of DML was assessed using DNA barcoding analysis. Four different solvent extracts of DML were prepared and subjected to antioxidant activity and phytochemical assays. Neuroprotective effects of DML extracts were evaluated using relevant biochemical and imaging assays that measure cell viability/death, ROS generation, Ca²⁺ levels, mitochondrial dysfunction, and AIF nuclear translocation.

RESULTS

The sequences of matK, rbcL, atpF-H, and psbK-I in DML were identical with those in voucher specimens, confirming that DML was indeed D. morbifera. The ethyl acetate extract of DML (DMLE) showed the highest flavonoid and phenolic content, and prominent DPPH/superoxide radical scavenging and reducing power activities. In the HT22 cell model, glutamate was shown to be the causative agent for apoptotic cell death via elevation of intracellular ROS and Ca²⁺ levels, induction of mitochondrial depolarization and membrane permeabilization, and translocation of AIF to the nucleus. Of note, N-acetyl-L-cysteine and necrostatin-1, but not z-VAD-fmk, completely prevented glutamate-induced cell death, implying that oxidative stress and AIF translocation were pivotal in glutamate cytotoxicity. DMLE significantly recovered glutamate-induced apoptotic cell death in a concentration-dependent manner. It completely inhibited intracellular/mitochondrial ROS generation, the elevation of Ca²⁺ levels, and mitochondrial dysfunction induced by glutamate during early exposure within 8 h. It significantly reversed subsequent AIF nuclear translocation after 12 h of treatment. Antioxidant activities of DMLE may be the protective mechanism that regulates homeostatic balance of ROS and Ca²⁺ as well as maintains mitochondrial function.

CONCLUSIONS

DMLE shows significant neuroprotective effects against glutamate-induced oxidative neuronal cell death. Therefore, DM could be a potential therapeutic candidate for neurological disorders propagated by glutamate toxicity.

Anti‑inflammatory effects of Dendropanax morbifera in lipopolysaccharide‑stimulated RAW264.7 macrophages and in an animal model of atopic dermatitis

Dendropanax morbifera (D. morbifera), known as Dendro, means 'omnipotent drug' (Panax), and has been called the panacea tree. Various studies on D. morbifera are currently ongoing, aiming to determine its medicinal uses. The present study investigated the anti‑inflammatory effects and underlying mechanism of a natural extract of D. morbifera leaves (DPL) in lipopolysaccharide (LPS)‑stimulated RAW264.7 macrophages. In the present study, the following assays and models were used: MTT assay, nitric oxide (NO) assay, western blotting, ELISA and mouse models of atopic dermatitis. DPL extract markedly reduced the production of NO, inducible NO synthase and interleukin‑6, as well as the nuclear translocation of nuclear factor‑κB (NF‑κB). Additionally, the LPS‑induced activation of extracellular signal‑regulated kinase 1/2 (ERK1/2), P38 and c‑Jun N‑terminal kinase (JNK) was suppressed by DPL extract. Taken together, these results indicate that NF‑κB, ERK1/2, P38 and JNK may be potential molecular targets of DPL extract in the LPS‑induced inflammatory response. Subsequently, the present study investigated the effects of DPL extract in a 2,4‑dinitrochlorobenzene‑induced atopic dermatitis mouse model. Ear thickness, serum immunoglobulin E levels and histological analysis revealed that the DPL extract was effective in attenuating the inflammatory response. These results indicate that DPL extract has anti‑inflammatory potential and may be developed as a botanical drug to treat atopic dermatitis.