SZAP exerts analgesic effects on rheumatalgia in CIA rats by suppressing pain hyperalgesia and inhibiting TRPV1 and P2X3

α7nAChR-mediated astrocytic activation: a novel mechanism of Xiongzhi Dilong decoction in ameliorating chronic migraine

ETHNOPHARMACOLOGICAL RELEVANCE

Alpha 7 nicotinic acetylcholine receptor (α7nAChR)-mediated astrocytic activation is closely related to central sensitization of chronic migraine (CM). Xiongzhi Dilong decoction (XZDL), originated from Xiongzhi Shigao decoction of Yi-zong-jin-jian, has been confirmed to relieve CM in experiment and clinic. However, its underlying mechanism for treating CM has not been elucidated.

AIM OF THE STUDY

To reveal the underlying mechanisms of XZDL to alleviate CM in vivo focusing mainly on α7nAChR-mediated astrocytic activation and central sensitization in TNC.

MATERIALS AND METHODS

CM rat model was established by subcutaneous injection of nitroglycerin (NTG) recurrently, and treated with XZDL simultaneously. Migraine-like behaviors of rats (ear redness, head scratching, and cage climbing) and pain-related reactions (mechanical hind-paw withdrawal threshold) of rats were evaluated before and after NTG injection and XZDL administration at different points in time for nine days. The immunofluorescence single and double staining were applied to detect the levels of CGRP, c-Fos, GFAP and α7nAChR in NTG-induced CM rats. ELISA kits were employed to quantify levels of TNF-α, IL-1β, and IL-6 in medulla oblongata of CM rats. The expression levels of target proteins were examined using western blotting. Finally, methyllycaconitine citrate (MLA, a specific antagonist of α7nAChR) was applied to further validate the mechanisms of XZDL in vivo.

RESULTS

XZDL significantly attenuated the pain-related behaviors of the NTG-induced CM rats, manifesting as constraints of aberrant migraine-like behaviors including elongated latency of ear redness and decreased numbers of head scratching and cage climbing, and increment of mechanical withdrawal threshold. Moreover, XZDL markedly lowered levels of CGRP and c-Fos, as well as inflammatory cytokines (IL-1β, IL-6 and TNF-α) in CM rats. Furthermore, XZDL significantly enhanced α7nAChR expression and its co-localization with GFAP, while markedly inhibited the expression of GFAP and the activation of JAK2/STAT3/NF-κB pathway in the TNC of CM rats. Finally, blocking α7nAChR with MLA reversed the effects of XZDL on astrocytic activation, central sensitization, and the pain-related behaviors in vivo.

CONCLUSION

XZDL inhibited astrocytic activation and central sensitization in NTG-induced CM rats by facilitating α7nAChR expression and suppressing JAK2/STAT3/NF-κB pathway, implying that the regulation of α7nAChR-mediated astrocytic activation represents a novel mechanism of XZDL for relieving CM.

Miao medicine Gu Yan Xiao tincture inhibits mTOR to stimulate chondrocyte autophagy in a rabbit model of osteoarthritis

ETHNOPHARMACOLOGICAL RELEVANCE

The Gu Yan Xiao tincture, a blend of traditional Chinese herbs, is traditionally used for osteoarthritis and related pain. This study investigated its mechanism of action in order to rationalize and validate its therapeutic use.

AIM OF THE STUDY

This study analyzed, in a rabbit model of knee osteoarthritis, whether and how Gu Yan Xiao tincture exerts therapeutic benefits by modulating chondrocyte autophagy.

MATERIALS AND METHODS

The active constituents within the GYX tincture were identified using liquid chromatography-mass spectrometry. The rabbit model was established by injecting animals with type II collagenase intra-articularly, and the effects of topically applied tincture were examined on osteoarthritis lesions of the knee using histopathology, micro-computed tomography and x-ray imaging. Effects of the tincture were also evaluated on levels of inflammatory cytokines, matrix metalloproteases, and autophagy in chondrocytes. As a positive control, animals were treated with sodium diclofenac.

RESULTS

The tincture mitigated the reduction in joint space, hyperplasia of the synovium and matrix metalloproteases in serum that occurred after injection of type II collagenase in rabbits. These therapeutic effects were associated with inhibition of mTOR and activation of autophagy in articular chondrocytes. Inhibiting mTOR with rapamycin potentiated the therapeutic effects of the tincture, while inhibiting autophagy with 3-methyladenine antagonized them.

CONCLUSIONS

Gu Yan Xiao tincture mitigates tissue injury in a rabbit model of osteoarthritis, at least in part by inhibiting mTOR and thereby promoting autophagy in chondrocytes. These results rationalize the use of the tincture not only against osteoarthritis but also potentially other diseases involving inhibition of autophagy in bones and joints.

Huang-Lian-Jie-Du decoction drug-containing serum inhibits IL-1β secretion from D-glucose and PA induced BV2 cells via autophagy/NLRP3 signaling

ETHNOPHARMACOLOGICAL RELEVANCE

Huang-Lian-Jie-Du decoction (HLJDD), a famous traditional Chinese medicine prescription with heat-clearing and detoxifying effects, has been widely used to treat diabetes, dementia, stroke, and other diseases. However, the detailed mechanisms of HLJDD against type 2 diabetes associated cognitive dysfunction (DACD) through inhibiting interleukin-1β (IL-1β) mediated neuroinflammation remain to be further elucidated.

AIM OF THE STUDY

The aim of this study was to investigate the effect and potential mechanism of HLJDD on IL-1β secretion in a DACD model of BV2 cells induced by D-glucose and palmitic acid (PA).

MATERIALS AND METHOD

sUltra-performance liquid chromatography-quadrupole/electrostatic field orbital well high-resolution mass spectrometry technology was used to analyze the compounds in HLJDD drug-containing serum. The cytotoxicity was detected by cell counting kit-8. Enzyme-linked immunosorbent assay was used to measure the secretion of IL-1β in BV2 cells. Reactive oxygen species, glutathione, superoxide dismutase, and malondialdehyde kits were used to detect the intracellular oxidative stress levels. The autophagy level was determined by autophagy staining kit and transmission electron microscope. The expression levels of autophagy-related 7 (Atg7), P62, LC3, nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3(NLRP3), Caspase1, and IL-1β were detected by real-time PCR, immunofluorescence, and western blotting. The Atg7siRNA was transfected into BV2 cells to produce autophagy inhibitory effect. Then the effect of HLJDD drug-containing serum on IL-1β secretion in D-glucose and PA induced BV2 cells and the potential mechanism of autophagy-NLRP3 inflammasome activation were further observed.

RESULTS

Eighty-eight compounds were preliminarily identified in HLJDD drug-containing serum, among which geniposide, baicalin, palmatine, berberine, wogonoside, wogonin, and geniposidic acid were identified as the main prototype components of HLJDD into the blood. In this study, the DACD model of BV2 cells induced by high concentrations of glucose and PA was successfully constructed. HLJDD drug-containing serum significantly reduced the secretion of IL-1β and the activity of NLRP3 inflammasome with improving the oxidative stress level. Interestingly, the enhanced autophagy level was also found. After transfection of Atg7siRNA into BV2 cells, the effect of HLJDD drug-containing serum on autophagy promotion was reversed, but the inhibitory effects on IL-1β secretion, NLRP3 inflammasome activation, and oxidative stress were reduced.

CONCLUSIONS

These results indicated that the inhibition of HLJDD drug-containing serum on the IL-1β secretion in D-glucose and PA induced BV2 cells was related to autophagy promotion, the decreased NLRP3 inflammasome activation, and the improved oxidative stress. Moreover, the improvement of HLJDD drug-containing serum on IL-1β secretion, NLRP3 inflammasome activation, and oxidative stress were all closely associated with Atg7 mediated autophagy promotion. Geniposide, baicalin, palmatine, berberine, wogonoside, wogonin, and geniposidic acid may be the potential active ingredients of HLJDD drug-containing serum.

The role of TRPV1 in RA pathogenesis: worthy of attention

Transient receptor potential cation channel subfamily V member 1 (TRPV1) is a Ca2+permeable, non-selective cation channel that is found primarily in sensory nerve fibres. Previous studies focused on pain transmission. However, recent studies have found that the TRPV1 channel, in addition to being associated with pain, also plays a role in immune regulation and their dysregulation frequently affects the development of rheumatoid arthritis (RA). A thorough understanding of the mechanism will facilitate the design of new TRPV1-targeted drugs and improve the clinical efficacy of RA. Here, we provide an updated and comprehensive overview of how the TRPV1 channel intrinsically regulates neuronal and immune cells, and how alterations in the TRPV1 channel in synoviocytes or chondrocytes extrinsically affect angiogenesis and bone destruction. Rapid progress has been made in research targeting TRPV1 for the treatment of inflammatory arthritis, but there is still much-uncharted territory regarding the therapeutic role of RA. We present a strategy for targeting the TRPV1 channel in RA therapy, summarising the difficulties and promising advances in current research, with the aim of better understanding the role of the TRPV1 channel in RA pathology, which could accelerate the development of TRPV1-targeted modulators for the design and development of more effective RA therapies.

Integration of transdermal chemistry and network pharmacology to decipher the mechanism of ShexiangZhuifeng analgesic plaster to treat rheumatoid arthritis

BACKGROUND

Transdermal patches are an effective form of treatment for rheumatoid arthritis (RA), and they have a number of benefits, including patient compliance, accessibility, and low systemic toxicity. ShexiangZhuifeng Analgesic Plaster (SZAP), a patch made up of many traditional medicines, has been successfully utilized in numerous clinical trials to treat RA. However, information about anti-RA processes and transdermal active components is still emerging.

PURPOSE

Our objectives were to identify the transdermal active components of SZAP and investigate its anti-RA mechanisms, primarily focused on joint inflammation.

METHODS

The collagen-induced arthritis (CIA) rats were created first, and then the arthritis score, Paw thickness, and morphology feature of joint synovial were assessed after 7 days of therapy with SZAP. Moreover, the Franz diffusion cell and UPLC-MS technologies were combined to identify and measure the transdermal active ingredients of SZAP. Furthermore, network pharmacology was utilized to anticipate the putative the mechanism of SZAP for treating RA. Finally, the results of network pharmacology were validated using LPS-induced RAW 264.7 cells and CIA rats.

RESULTS

SZAP significantly reduced paw thickness, arthritic score and pathological characteristics of joint synovitis in (CIA) rats. Additionally, 12 transdermal active components of SZAP were identified, and network pharmacology prediction results suggested that SZAP may alleviate joint synovial inflammation by blocking the Akt/mTOR/HIF-1 pathway. Our investigations' findings demonstrated that SZAP dramatically reduced the concentrations of excess cytokines (IL6, VEGF, and TNF-α), as well as the protein overexpression of the AKT/mTOR/HIF- pathway (HIF-1, p-AKT, and p-mTOR), whereas its anti-inflammation effect was reversed once AKT or mTOR was activated.

CONCLUSION

By blocking the AKT/mTOR/HIF-1 pathway, SZAP can lessen the release of inflammatory mediators, which reduces joint synovial inflammation associated with RA. The pharmacological evaluation of TCM transdermal drug delivery formulations like SZAP may be amenable to the integration of transdermal chemistry and network pharmacology approaches.