Muscle atrophy is an abnormal condition characterized by loss of skeletal muscle mass and function and is primarily caused by injury, malnutrition, various diseases, and aging. Leaf of lotus (Nelumbo nucifera Gaertn), which has been used for medicinal purposes, contains various active ingredients, including polyphenols, and is reported to exert an antioxidant effect. In this study, we investigated the effect of water extract of lotus leaf (LL) on muscle atrophy and the underlying molecular mechanisms of action. Amounts of 100, 200, or 300 mg/kg/day LL were administered to dexamethasone (DEX)-induced muscle atrophy mice for 4 weeks. Micro-computed tomography (CT) analysis revealed that the intake of LL significantly increased calf muscle volume, surface area, and density in DEX-induced muscle atrophy mice. Administration of LL recovered moving distance, grip strength, ATP production, and body weight, which were decreased by DEX. In addition, muscle damage caused by DEX was also improved by LL. LL reduced the protein catabolic pathway by suppressing gene expression of muscle atrophy F-Box (MAFbx; atrogin-1), muscle RING finger 1 (MuRF1), and forkhead box O (FoxO)3a, as well as phosphorylation of AMP-activated kinase (AMPK). The AKT-mammalian target of the rapamycin (mTOR) signal pathway, which is important for muscle protein synthesis, was increased in LL-administered groups. The HPLC analysis and pharmacological test revealed that quercetin 3-O-beta-glucuronide (Q3G) is a major active component in LL. Thus, Q3G decreased the gene expression of atrogin-1 and MuRF1 and phosphorylation of AMPK. This compound also increased phosphorylation levels of mTOR and its upstream enzyme AKT in DEX-treated C2C12 cells. We identified that LL improves muscle wasting through regulation of muscle protein metabolism in DEX-induced muscle atrophy mice. Q3G is predicted to be one of the major active phenolic components in LL. Therefore, we propose LL as a supplement or therapeutic agent to prevent or treat muscle wasting, such as sarcopenia.

Several Cissus species have been used and reported to possess medicinal benefits. However, the anti-inflammatory mechanisms of Cissus subtetragona have not been described. In this study, we examined the potential anti-inflammatory effects of C. subtetragona ethanol extract (Cs-EE) in vitro and in vivo, and investigated its molecular mechanism as well as its flavonoid content. Lipopolysaccharide (LPS)-induced macrophage-like RAW264.7 cells and primary macrophages as well as LPS-induced acute lung injury (ALI) and HCl/EtOH-induced acute gastritis mouse models were utilized. Luciferase assays, immunoblotting analyses, overexpression strategies, and cellular thermal shift assay (CETSA) were performed to identify the molecular mechanisms and targets of Cs-EE. Cs-EE concentration-dependently reduced the secretion of NO and PGE₂, inhibited the expression of inflammation-related cytokines in LPS-induced RAW264.7 cells, and decreased NF-κB- and AP-1-luciferase activity. Subsequently, we determined that Cs-EE decreased the phosphorylation events of NF-κB and AP-1 pathways. Cs-EE treatment also significantly ameliorated the inflammatory symptoms of HCl/EtOH-induced acute gastritis and LPS-induced ALI mouse models. Overexpression of HA-Src and HA-TAK1 along with CETSA experiments validated that inhibited inflammatory responses are the outcome of attenuation of Src and TAK1 activation. Taken together, these findings suggest that Cs-EE could be utilized as an anti-inflammatory remedy especially targeting against gastritis and acute lung injury by attenuating the activities of Src and TAK1.

An ethanol extract (Pd-EE) of Pinus densiflora Siebold and Zucc was derived from the branches of pine trees. According to the Donguibogam, pine resin has the effects of lowering the fever, reducing pain, and killing worms. The purpose of this study is to investigate whether Pd-EE has anti-inflammatory effects. During in vitro trials, NO production, as well as changes in the mRNA levels of inflammation-related genes and the phosphorylation levels of related proteins, were confirmed in RAW264.7 cells activated with lipopolysaccharide depending on the presence or absence of Pd-EE treatment. The activities of transcription factors were checked in HEK293T cells transfected with adapter molecules in the inflammatory pathway. The anti-inflammatory efficacy of Pd-EE was also estimated in vivo with acute gastritis and acute lung injury models. LC-MS analysis was conducted to identify the components of Pd-EE. This extract reduced the production of NO and the mRNA expression levels of iNOS, COX-2, and IL-6 in RAW264.7 cells. In addition, protein expression levels of p50 and p65 and phosphorylation levels of FRA1 were decreased. In the luciferase assay, the activities of NF-κB and AP-1 were lowered. In acute gastritis and acute lung injury models, Pd-EE suppressed inflammation, resulting in alleviated damage.

Many indigenous Korean plants have been used in medicinal preparations and health-promoting foods. These plant species contain beneficial metabolites with various bioactivities, such as antioxidant and anti-inflammatory activities. Herein, we suggest a new screening strategy using metabolomics to explore the bioactive compounds in 50 Korean plants. Secondary metabolites were analyzed using UHPLC-LTQ-Orbitrap-MS/MS. The plant extracts were subjected to antioxidant and anti-inflammatory assays. We identified metabolites that contributed to bioactivities according to the results of bioassays and multivariate analyses. Using Pearson’s correlation, phenolics (e.g., casuarictin, 3-O-methylellagic acid) showed positive correlation with antioxidant activity, while biflavonoids (e.g., amentoflavone, rosbustaflavone) were correlated with nitric oxide (NO) inhibition activity. To compensate for the limitation of this new strategy, we further validated these by investigating three parts (branches, fruits, leaves) of Platycladus orientalis which showed high activities on both bioassays. Unlike the above observation, we identified significantly different metabolites from different parts, which was not the results of bioassays. In these validation steps, interestingly, biflavonoids (e.g., robustaflavone, sciadopitysin) contributed to both activities in P. orientalis. The findings of this work suggest that new strategy could be more beneficial in the identification of bioactive plant species as well as that of their corresponding bioactive compounds that impart the bioactivity.

Many species in the genus Guettarda are known to exert anti-inflammatory effects and are used as traditional medicinal plants to treat various inflammatory symptoms. However, no studies on the inflammatory activities of Guettarda crispiflora Vahl have been reported. The aim of the study was to investigate in vitro and in vivo the anti-inflammatory effects of a methanol extract of Guettarda crispiflora Vahl (Gc-ME). To determine the anti-inflammatory activity of Gc-ME, lipopolysaccharide (LPS)-, poly(I:C)-, or Pam3CSK4-treated RAW264.7 cells, HCl/EtOH- and LPS-treated mice were employed for in vitro and in vivo tests. LPS-induced nitric oxide production in RAW264.7 cells was determined by Griess assays and cytokine gene expression in LPS-activated RAW264.7 cells, confirmed by RT- and real-time PCR. Transcriptional activation was evaluated by luciferase reporter gene assay. Target protein validation was assessed by Western blot analysis and cellular thermal shift assays (CETSA) with LPS-treated RAW264.7 and gene-transfected HEK293 cells. Using both a HCl/EtOH-induced gastritis model and an LPS-induced lung injury model, inflammatory states were checked by scoring or evaluating gastric lesions, lung edema, and lung histology. Phytochemical fingerprinting of Gc-ME was observed by using liquid chromatography–mass spectrometry. Nitric oxide production induced by LPS and Pam3CSK4 in RAW264.7 cells was revealed to be reduced by Gc-ME. The LPS-induced upregulation of iNOS, COX-2, IL-6, and IL-1β was also suppressed by Gc-ME treatment. Gc-ME downregulated the promotor activities of AP-1 and NF-κB triggered by MyD88- and TRIF induction. Upstream signaling proteins for NF-κB activation, namely, p-p50, p-p65, p-IκBα, and p-Src were all downregulated by Ch-EE. Moreover, Src was revealed to be directly targeted by Gc-ME. This extract, orally treated strongly, attenuated the inflammatory symptoms in HCl/EtOH-treated stomachs and LPS-treated lungs. Therefore, these results strongly imply that Guettarda crispiflora can be developed as a promising anti-inflammatory remedy with Src-suppressive properties.