Portulaca oleracea is as a medicinal plant known for its neuroprotective, hepatoprotective, antidiabetic, antioxidant, anticancer, antimicrobial, antiulcerogenic, and anti-inflammatory activities. However, the specific active compounds responsible for the individual pharmacological effects of P. oleracea extract (95% EtOH) remain unknown. Here, we hypothesized that alkaloids, the most abundant constituents in P. oleracea extract, are responsible for its anti-inflammatory activity. We investigated the phytochemical substituents (compounds 1–22) using nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS) and screened their effects on NO production in lipopolysaccharide (LPS)-induced macrophages. Compound 20, 1-carbomethoxy-β-carboline, as an alkaloid structure, ameliorated nitric oxide (NO) production, inducible nitric oxide synthase (iNOS), and proinflammatory cytokines associated with the mitogen-activated protein kinase (MAPK) pathways, p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). Subsequently, we observed that compound 20 suppressed nuclear translocation of nuclear factor κB (NF-κB) using immunocytochemistry. Moreover, we recently reported that compound 8, trans-N-feruloyl-3’, 7’-dimethoxytyramine, was originally purified from P. oleracea extracts. Our results suggest that 1-carbomethoxy-β-carboline, the most effective anti-inflammatory agent among alkaloids in the 95% EtOH extract of P. oleracea, was suppressing the MAPK pathway and nuclear translocation of NF-κB. Therefore, P. oleracea extracts and specifically 1-carbomethoxy-β-carboline may be novel therapeutic candidates for the treatment of inflammatory diseases associated with the activation of MAPKs and NF-κB.

Many studies have reported the biological activities of retrofractamide C (RAC). However, few studies have investigated the anti-inflammatory effect of RAC. In the present study, we investigated the anti-inflammatory effect of RAC using lipopolysaccharide (LPS)-induced J774A.1 cells and a xylene-induced mouse ear edema model. Treatment with RAC decreased LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) secretion and inducible NO synthase (iNOS) and cyclooxygenase 2 (COX2) protein expression. It also downregulated the LPS-induced production of interleukin-1β (IL-1β) and interleukin-6 (IL-6) but not tumor necrosis factor α (TNF-α). In the LPS-induced signaling pathway, RAC inhibited the phosphorylation of extracellular signal-regulated kinase (ERK) and nuclear factor kappa light chain enhancer of activated B cells (NF-κB) but not c-Jun N-terminal kinase (JNK) or p38. In a xylene-induced mouse ear edema model, RAC treatment alleviated edema formation and inflammatory cell infiltration. In conclusion, the present study indicates that RAC has the potential to have anti-inflammatory effects and could be a prospective functional food.

Eudebeiolide B is a eudesmane-type sesquiterpenoid compound isolated from Salvia plebeia R. Br., and little is known about its biological activity. In this study, we investigated the effects of eudebeiolide B on osteoblast differentiation, receptor activator nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis in vitro and ovariectomy-induced bone loss in vivo. Eudebeiolide B induced the expression of alkaline phosphatase (ALP) and calcium accumulation during MC3T3-E1 osteoblast differentiation. In mouse bone marrow macrophages (BMMs), eudebeiolide B suppressed RANKL-induced osteoclast differentiation of BMMs and bone resorption. Eudebeiolide B downregulated the expression of nuclear factor of activated T-cells 1 (NFATc1) and c-fos, transcription factors induced by RANKL. Moreover, eudebeiolide B attenuated the RANKL-induced expression of osteoclastogenesis-related genes, including cathepsin K (Ctsk), matrix metalloproteinase 9 (MMP9) and dendrocyte expressed seven transmembrane protein (DC-STAMP). Regarding the molecular mechanism, eudebeiolide B inhibited the phosphorylation of Akt and NF-κB p65. In addition, it downregulated the expression of cAMP response element-binding protein (CREB), Bruton’s tyrosine kinase (Btk) and phospholipase Cγ2 (PLCγ2) in RANKL-induced calcium signaling. In an ovariectomized (OVX) mouse model, intragastric injection of eudebeiolide B prevented OVX-induced bone loss, as shown by bone mineral density and contents, microarchitecture parameters and serum levels of bone turnover markers. Eudebeiolide B not only promoted osteoblast differentiation but inhibited RANKL-induced osteoclastogenesis through calcium signaling and prevented OVX-induced bone loss. Therefore, eudebeiolide B may be a new therapeutic agent for osteoclast-related diseases, including osteoporosis, rheumatoid arthritis and periodontitis.

Osteoporosis is characterized by the deterioration of bone structures and decreased bone mass, leading to an increased risk of fracture. Estrogen deficiency in postmenopausal women and aging are major factors of osteoporosis and are some of the reasons for reduced quality of life. In this study, we investigated the effects of n-trans-hibiscusamide (NHA) and its derivative 4-O-(E)-feruloyl-N-(E)-hibiscusamide (HAD) on receptor activator of nuclear factor kappa-Β (NF-κB) ligand (RANKL)-induced osteoclast differentiation and an ovariectomized osteoporosis mouse model. NHA and HAD significantly inhibited the differentiation of osteoclasts from bone marrow-derived macrophages (BMMs) and the expression of osteoclast differentiation-related genes. At the molecular level, NHA and HAD significantly downregulated the phosphorylation of mitogen-activated protein kinase (MAPK) signaling molecules. However, Akt and NF-κB phosphorylation was inhibited only after NHA or HAD treatment. In the ovariectomy (OVX)-induced osteoporosis model, both NHA and HAD effectively improved trabecular bone structure. C-terminal telopeptide (CTX), a bone resorption marker, and RANKL, an osteoclast stimulation factor, were significantly reduced by NHA and HAD. The tartrate-resistant acid phosphatase (TRAP)-stained area, which indicates the osteoclast area, was also decreased by these compounds. These results show the potential of NHA and HAD as therapeutic agents for osteoporosis.

Lindera obtusiloba Blume has several activities, such as anti-inflammatory, anti-allergic, anti-tumor, anti-wrinkle, and antioxidant activities. Interleukin-6 (IL-6) is a classic pro-inflammatory cytokine that is associated with various functions, such as proliferation, invasion, inflammatory responses and functions within antioxidant defense systems. In this study, we investigated IL-6-induced STAT3 activation of lignan compounds isolated from L. obtusiloba. The structures of the isolated compounds were elucidated via spectroscopic nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS). As a result, seven lignans were identified from L. obtusiloba. All the isolated compounds (1–7) were evaluated for their IL-6-induced STAT3 inhibitory effects in Hep3B cells using a luciferase reporter assay. Of the isolates, compounds 1 and 5 showed inhibitory effects against IL-6-stimulated STAT3 activation. Furthermore, the mRNA expression levels of inflammation-related genes such as CRP, IL-1b, and SOCS3 were significantly reduced by exposure to compounds 1 and 5. The protein levels of p-STAT3 and p-JAK2 in IL-6-induced U266 cells were regulated in the presence of lignans derived from Lindera obtusiloba by Western blot assay. Based on the results, this study of L. obtusiloba demonstrates that the species has promise as a bioactive candidate for the treatment of IL-6-induced STAT3-related disease.

In this study, we investigated whether three microbial strains, Lactiplantibacillus plantarum J-135, Saccharomyces cerevisiae DAE-4, and Bacillus velezensis PBS-17, could be used to reduce mold growth and spoilage during the production of fermented feed. These microorganisms were isolated and characterized via an evaluation of their antibacterial activity, enzymatic activity, bile acid resistance, and acid tolerance. L. plantarum J-135 and S. cerevisiae DAE-4 demonstrated excellent acid tolerance and bile acid resistance, and L. plantarum J-135 exhibited antibacterial activity against Salmonella species. B. velezensis PBS-17 showed the greatest protease, cellulase, α-amylase, and phytase enzymatic activities, and displayed antibacterial activity against Fusarium solani, Aspergillus flavus, Penicillium sp., and Fusarium oxysporum. The three isolated strains were diluted to the same concentration (1:1:1) to create a culture solution, which was added to a standard feed (experimental group) to prepare fermented feed. This was compared with feed treated with a commercially available single probiotic preparation (control group 1) or a mixed microbial preparation that was composed of multiple strains, including B. subtilis. The feed treated with the single probiotic preparation spoiled after 21 days due to insufficient lactic acid bacteria growth, whereas the feed treated with the mixed microbial preparation exhibited mold growth after 14 days. The bacteria and fungi that cause spoilage during fermented feed production were effectively controlled in feed treated with L. plantarum J-135, S. cerevisiae DAE-4, and B. velezensis PBS-17. Therefore, the mixture of these three microbial strains may reduce the risk of spoilage during fermented silage and feed processing, thereby improving storage properties and stability.