Sesquiterpenes from Chloranthus holostegius with anti-inflammatory activities.

The phytoconstituents of the whole plants of Chloranthus holostegius were investigated. As a result, thirteen undescribed sesquiterpenes (chloranholosins A-M, 1-13), including ten acorane-type sesquiterpenes (1-10), one germacrene-type sesquiterpene (11), and two lindenane-type sesquiterpenes (12-13), together with fifteen known sesquiterpenes were isolated. Their structures and absolute configurations were elucidated by a comprehensive method including the spectroscopic data, electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction. Chloranholosin L (12) was elucidated as a rare lindenane-type sesquiterpene featuring 14α-Me and 5-OH moieties. And chloranholosin M (13) was the first lindenane-type sesquiterpene possessing ß-cyclopropane, 14α-Me, and 5ß-H configuration from the family Chloranthaceae. Furthermore, twelve new isolates and some known sesquiterpenes were evaluated for their inhibitory activity against LPS-induced nitric oxide (NO) production in RAW 264.7 macrophage cells. Among them, compounds 12, 16, and 23 showed comparable inhibitory activity to that of the positive control, with IC50 values of 47.9, 41.5, and 48.3 µM, respectively.

Cinobufotalin prevents bone loss induced by ovariectomy in mice through the BMPs/SMAD and Wnt/ß-catenin signaling pathways.

BACKGROUND: Osteoporosis is a chronic bone disease characterized by bone loss and decreased bone strength. However, current anti-resorptive drugs carry a risk of various complications. The deep learning-based efficacy prediction system (DLEPS) is a forecasting tool that can effectively compete in drug screening and prediction based on gene expression changes. This study aimed to explore the protective effect and potential mechanisms of cinobufotalin (CB), a traditional Chinese medicine (TCM), on bone loss. METHODS: DLEPS was employed for screening anti-osteoporotic agents according to gene profile changes in primary osteoporosis. Micro-CT, histological and morphological analysis were applied for the bone protective detection of CB, and the osteogenic differentiation/function in human bone marrow mesenchymal stem cells (hBMMSCs) were also investigated. The underlying mechanism was verified using qRT-PCR, Western blot (WB), immunofluorescence (IF), etc. RESULTS: A safe concentration (0.25 mg/kg in vivo, 0.05 µM in vitro) of CB could effectively preserve bone mass in estrogen deficiency-induced bone loss and promote osteogenic differentiation/function of hBMMSCs. Both BMPs/SMAD and Wnt/ß-catenin signaling pathways participated in CB-induced osteogenic differentiation, further regulating the expression of osteogenesis-associated factors, and ultimately promoting osteogenesis. CONCLUSION: Our study demonstrated that CB could significantly reverse estrogen deficiency-induced bone loss, further promoting osteogenic differentiation/function of hBMMSCs, with BMPs/SMAD and Wnt/ß-catenin signaling pathways involved.

Licochalcone Mediates the Pain Relief by Targeting the Voltage-Gated Sodium Channel.

Licorice is a traditional Chinese medicine and recorded to have pain relief effects in national pharmacopoeia, but the mechanisms behind these effects have not been fully explored. Among the hundreds of compounds in licorice, licochalcone A (LCA) and licochalcone B (LCB) are two important components belonging to the chalcone family. In this study, we compared the analgesic effects of these two licochalcones and the molecular mechanisms. LCA and LCB were applied in cultured dorsal root ganglion (DRG) neurons, and the voltage-gated sodium (NaV) currents and action potentials were recorded. The electrophysiological experiments showed that LCA can inhibit NaV currents and dampen excitabilities of DRG neurons, whereas LCB did not show inhibition effect on NaV currents. Because the NaV1.7 channel can modulate Subthreshold membrane potential oscillations in DRG neuron, which can palliate neuropathic pain, HEK293T cells were transfected with NaV1.7 channel and recorded with whole-cell patch clamp. LCA can also inhibit NaV1.7 channels exogenously expressed in HEK293T cells. We further explored the analgesic effects of LCA and LCB on formalin-induced pain animal models. The animal behavior tests revealed that LCA can inhibit the pain responses during phase 1 and phase 2 of formalin test, and LCB can inhibit the pain responses during phase 2. The differences of the effects on NaV currents between LCA and LCB provide us with the basis for developing NaV channel inhibitors, and the novel findings of analgesic effects indicate that licochalcones can be developed into effective analgesic medicines. SIGNIFICANCE STATEMENT: This study found that licochalcone A (LCA) can inhibit voltage-gated sodium (NaV) currents, dampen excitabilities of dorsal root ganglion neurons, and inhibit the NaV1.7 channels exogenously expressed in HEK293T cells. Animal behavior tests showed that LCA can inhibit the pain responses during phase 1 and phase 2 of formalin test, whereas licochalcone B can inhibit the pain responses during phase 2. These findings indicate that licochalcones could be the leading compounds for developing NaV channel inhibitors and effective analgesic medicines.

The immunosuppressive effects and mechanisms of loureirin B on collagen-induced arthritis in rats.

Introduction: Rheumatoid arthritis (RA) is a common disease mainly affecting joints of the hands and wrists. The discovery of autoantibodies in the serum of patients revealed that RA belonged to the autoimmune diseases and laid a theoretical basis for its immunosuppressive therapy. The pathogenesis of autoimmune diseases mainly involves abnormal activation and proliferation of effector memory T cells, which is closely related to the elevated expression of Kv1.3, a voltage-gated potassium (Kv) channel on the effector memory T cell membrane. Drugs blocking the Kv1.3 channel showed a strong protective effect in RA model animals, suggesting that Kv1.3 is a target for the discovery of specific RA immunosuppressive drugs. Methods: In the present study, we synthesized LrB and studied the effects of LrB on collagen- induced arthritis (CIA) in rats. The clinical score, paw volume and joint morphology of CIA model rats were compared. The percentage of CD3+, CD4+ and CD8+ T cells in rat peripheral blood mononuclear and spleen were analyzed with flow cytometry. The concentrations of inflammatory cytokines interleukin (IL)-1b, IL-2, IL-4, IL-6, IL-10 and IL-17 in the serum of CIA rats were analyzed with enzyme-linked immunosorbent assay. The IL-1b and IL-6 expression in joints and the Kv1.3 expression in peripheral blood mononuclear cells (PBMCs) were quantified by qPCR. To further study the mechanisms of immunosuppressive effects of LrB, western blot and immunofluorescence were utilized to study the expression of Kv1.3 and Nuclear Factor of Activated T Cells 1 (NFAT1) in two cell models - Jurkat T cell line and extracted PBMCs. Results: LrB effectively reduced the clinical score and relieved joint swelling. LrB could also decrease the percentage of CD4+ T cells, while increase the percentage of CD8+ T cells in peripheral blood mononuclear and spleen of rats with CIA. The concentrations of inflammatory cytokines interleukin (IL)-1b, IL-2, IL-6, IL-10 and IL-17 in the serum of CIA rats were significantly reduced by LrB. The results of qPCR showed that Kv1.3 mRNA in the PBMCs of CIA rats was significantly higher than that of the control and significantly decreased in the LrB treatment groups. In addition, we confirmed in cell models that LrB significantly decreased Kv1.3 protein on the cell membrane and inhibited the activation of Nuclear Factor of Activated T Cells 1 (NFAT1) with immune stimulus. Conclusion: In summary, this study revealed that LrB could block NFAT1 activation and reduce Kv1.3 expression in activated T cells, thus inhibiting the proliferation of lymphocytes and the release of inflammatory cytokines, thereby effectively weakening the autoimmune responses in CIA rats. The effects of immunosuppression due to LrB revealed its potential medicinal value in the treatment of RA.

Luteolin relieves lung cancer-induced bone pain by inhibiting NLRP3 inflammasomes and glial activation in the spinal dorsal horn in mice.

BACKGROUND: Bone cancer pain (BCP) is one of the most severe complications in cancer patients. However, the pharmacological therapeutic approaches are limited. Luteolin, a major component of flavones, is widely distributed in plants and plays a critical role in the antinociceptive effects, but whether luteolin could alleviate cancer pain and its underlying mechanisms are not known. HYPOTHESIS/PURPOSE: This study investigated the molecular mechanisms by which luteolin reduced BCP. METHODS: Behavioral, pharmacological, immunohistochemical, and biochemical approaches were used to investigate the effect of luteolin on BCP. RESULTS: Luteolin treatment ameliorated Lewis lung cancer (LLC)-induced bone pain in mice in a dose-dependent manner. Luteolin treatment could inhibit the activation of neurons, glial cells, and NOD-like receptor protein 3 (NLRP3) inflammasomes in the dorsal spinal cord in the BCP mouse model. Furthermore, phosphorylated p-38 mitogen-activated protein kinase (MAPK) in the spinal dorsal horn (SDH) was suppressed by luteolin treatment that could influence the analgesic and glial inhibition effects of luteolin. CONCLUSION: Our results demonstrated that luteolin inhibited neuroinflammation by obstructing glial cell and NLRP3 inflammasome activation via modulating p38 MAPK activity in SDH, ultimately improving LLC-induced BCP.

NIR light-assisted phototherapies for bone-related diseases and bone tissue regeneration: A systematic review.

Recently, the rapid development of biomaterials has induced great interest in the precisely targeted treatment of bone-related diseases, including bone cancers, infections, and inflammation. Realizing noninvasive therapeutic effects, as well as improving bone tissue regeneration, is essential for the success of bone­related disease therapies. In recent years, researchers have focused on the development of stimuli-responsive strategies to treat bone-related diseases and to realize bone regeneration. Among the various external stimuli for targeted therapy, near infrared (NIR) light has attracted considerable interests due to its high tissue penetration capacity, minimal damage toward normal tissues, and easy remote control properties. The main objective of this systematic review was to reveal the current applications of NIR light-assisted phototherapy for bone-related disease treatment and bone tissue regeneration. Database collection was completed by June 1, 2020, and a total of 81 relevant studies were finally included. We outlined the various therapeutic applications of photothermal, photodynamic and photobiomodulation effects under NIR light irradiation for bone­related disease treatment and bone regeneration, based on the retrieved literatures. In addition, the advantages and promising applications of NIR light-responsive drug delivery systems for spatiotemporal-controlled therapy were summarized. These findings have revealed that NIR light-assisted phototherapy plays an important role in bone-related disease treatment and bone tissue regeneration, with significant promise for further biomedical and clinical applications.

Pathological Changes in Internal Organs after Blocking Low Hydraulic Resistance Channels along the Stomach Meridian in Pigs.

Objective. The correlation between meridians and organs (Zang-fu) is an important aspect of meridian theory. The objective of this paper is to investigate the pathological changes in the organs resulting from blocking low hydraulic resistance channel (LHRC) along the stomach meridian by injecting gel in pigs so as to offer some insight into the correlation between meridians and internal organs. Methods. Four white piglets and twelve black minipigs were divided into four batches and were observed in different periods. Each batch included two pairs of pigs and each pair matched two pigs with similar conditions among which gel was injected into 6~8 low hydraulic resistance points along the the stomach meridian in the experimental pig and the same amount of saline was injected into the same points in the control pig. The state of stomach and intestine was observed 6~10 weeks after the blocking model was developed. Results. The results showed that there were bloated stomach or/and intestine in all the experimental pigs while there were normal states in seven control pigs except one dead during the experiment. Conclusion. The findings confirmed that the blockage of LHRC along the stomach meridian can influence the state of stomach and intestine, leading to a distension on stomach or/and intestine.