Artocarpus tonkinensis Extract Inhibits LPS-Triggered Inflammation Markers and Suppresses RANKL-Induced Osteoclastogenesis in RAW264.7

Abstract

Artocarpus tonkinensis (At) leaf decoction, a traditional remedy prepared in North Vietnam by the Hmong ethnic group, is a tea extract rich in bioactive compounds that may have therapeutic effects in arthritis and backache. Indeed, it has been demonstrated that At is able to inhibit Th17 lymphocytes development and to protect mice in an experimental model of collagen-induced arthritis. By resorting to macrophage in vitro models of inflammation and osteoclastogenesis, we showed that At extract significantly reduced nitric oxide synthase 2 (NOS2) activity and IL-6 production by RAW 264.7 murine cells. Moreover, At demonstrated an anti-osteoclastogenic effect, as revealed by complete inhibition of TRAP-positive osteoclast formation and decreased expression of key osteoclast-related genes. This At activity likely relies on the inhibition of RANK downstream signaling pathway, as the activation of non-receptor tyrosine kinase Src is reduced upon RANKL-At exposure. Protective effect of At against bone loss was also enlightened in vivo by collagen-induced arthritis (CIA) experiment demonstrating that, although paw edema was only weakly opposed by drinking At decoction, bone and cartilage were well preserved in CIA+At mice and joint tissue expressed decreased levels of osteoclast marker genes respect to CIA control group. Maesopsin 4-O-β-D-glucoside (i.e., TAT-2, one of the main decoction bioactive components) was capable to contrast NOS2 activity, IL-6 expression and osteoclast formation, too, albeit to a lesser extent when compared to At decoction. Overall, this study enlightens another At cell target, macrophages, beside Th17 lymphocytes, and suggests that the anti-arthritic beneficial effects of At decoction largely derives from its ability to counteract not only inflammation, but also osteoclastogenesis.

Crocus sativus L. Petal Extract Inhibits Inflammation and Osteoclastogenesis in RAW 264.7 Cell Model

“…Notably, although many of these studies use experimental models involving pro-inflammatory immune responses, only two works have thus far investigated macrophages as one of the possible cell targets of Crocus sativus L. petal derivatives, showing that two purified polysaccharides, not a whole petal extract, augmented the immunogenic functions of macrophage RAW 264.7 cells [42,43]. Thus, based on our recent research on the anti-arthritic activities of another plant extract [27], and pointing toward a possible application for saffron harvesting waste, the present study has investigated the ability of an ethanolic extract obtained from Crocus sativus L. petals in modulating specific macrophage cellular mechanisms involved in inflammation and osteoclastogenesis. Moreover, our study proposes the idea of integrating saffron harvesting waste (i.e., petals) into a circular economy system to be converted into a raw material for a phytopharmaceutical extract, useful in the control of inflammation and bone loss.…”

“…In particular, Acp5 decreased in a dose-dependent manner, and its very low expression at 320 µg/mL mirrored the almost complete absence of TRAP-positive cells revealed by TRAP staining (Figure 6a). To further confirm the anti-osteoclastogenic effect of CsPE in this experimental model, we evaluated the expression of other markers of osteoclast formation and function, including calcitonin receptor (Calcr) (Figure 7b), matrix metallopeptidase 9 (Mmp9) (Figure 7c), and cathepsin K (Ctsk) (Figure 7d) [27]. Calcr gene, encoding for a protein involved in maintaining calcium homeostasis and in regulating osteoclast-mediated bone resorption, underwent a highly significant reduction (p < 0.0001) in the CsPE concentration range of 40-160 µg/mL and became undetectable at 320 µg/mL (Figure 7b).…”

“…After total RNA extraction by TRIzol (Invitrogen, Carlsbad, CA, USA) and reverse transcription to cDNA by QuantiTect Reverse Transcription Kit (Qiagen, Hilden, Germa-nia), a real-time PCR was performed using SYBR Green (Bio-Rad, Hercules, CA, USA) detection and the following specific primers: Gapdh forward 5 -CTGCCCAGAACATCATCCCT-3 ; Gapdh reverse 5 -ACTTGGCAGGTTTCTCCAGG-3 ; Acp5 forward 5 -CTGCCTTGTCAAGA-ACTTGC-3 ; Acp5 reverse 5 -ACCTTTCGTTGATGTCGCAC-3 ; Calcr forward 5 -TCATCAT-CCACCTGGTTGAG-3 ; Calcr reverse 5 -CACAGCCATGACAATCAGAG-3 ; Mmp9 for-ward 5 -GCTGACTACGATAAGGACGGCA-3 ; Mmp9 reverse 5 -GCGGCCCTCAAAGAT-GAACGG-3 ; Ctsk forward 5 -AGAAGACTCACCAGAAGCAG-3 ; and Ctsk reverse 5 -CAGGTTATGGGCAGAGATTTG-3 [27]. Values were calculated as the ratio of the specific gene to Gapdh expression, as determined by the relative quantification method (∆∆CT; means ± SD of triplicate determination) [28].…”

KYMASIN UP Natural Product Inhibits Osteoclastogenesis and Improves Osteoblast Activity by Modulating Src and p38 MAPK

“…Interestingly, the three herbal extracts combined in the KYMASIN UP and their active compounds have been reported to modulate OBs and/or OCs activities as well as bone structure [ 9 , 10 , 11 , 12 , 13 ]. The aim of the present study is to assess the effectiveness of KYMASIN UP in the differentiation process and activity of OCs and OBs by using established in vitro models consisting of the RAW 264.7 monocyte cell line conditioned with RANKL (receptor activator of nuclear factor kappa-Β ligand) protein [ 14 , 15 ] and C2C12 myoblasts treated with BMP2 (bone morphogenetic protein 2) [ 16 , 17 ], respectively. The molecular mechanisms underlying the effects of KYMASIN UP and its efficacy in human primary OBs were also investigated.…”

The complete chloroplast genome of Artocarpus tonkinensis, a tree native to China with diverse beneficial medicinal applications

“… 2017 ; Orecchini et al. 2020 ). Besides, it is also an ornamental street tree with a big and dense canopy.…”