Chemical Investigation and Antinociceptive Activity Evaluation of Marrubium Vulgare L. Aqueous Extract.

Marrubium vulgare L. (Lamiaceae) has a long history of use in traditional herbal medicine for the treatment of respiratory tract infections, inflammatory conditions, and pain. This study aimed to investigate the chemical composition, acute toxicity, and antinociceptive effects of the aqueous extract from M. vulgare leaves (AEMV). Antioxidant activity was evaluated using DPPH and reducing power assays. The chemical composition of AEMV was determined through LC-MS/MS, and the levels of total phenolics, flavonoids, and condensed tannins were quantified. Acute oral toxicity was assessed in male Swiss mice with a single oral dose of AEMV (1, 2, 5 g/kg). The analgesic impact was examined through writhing, hot plate, and formalin tests. Our findings not only confirmed the safety of the extract in animal models but also revealed significant antioxidant activity in AEMV. High-performance liquid chromatography (HPLC) analysis identified important bioactive compounds, with marrubiin being a major component. Furthermore, AEMV demonstrated robust antinociceptive properties in all conducted tests, highlighting its potential as a valuable natural source of bioactive compounds suitable for a wide range of therapeutic applications.

[Effects of tetramethylpyrazine on pharmacokinetics in plasma and brain dialysate and neuropathic pain in rat model of spared sciatic nerve injury].

This study aims to explore the effects of tetramethylpyrazine(TMP) on pharmacokinetics in plasma and brain dialysate and neuropathic pain in the rat model of partial sciatic nerve injury(SNI), and to investigate the correlation between the analgesic effect of TMP and its concentrations in the plasma and brain dialysate. Male SD rats were randomized into Sham, SNI, and SNI+TMP groups. Mechanical stimulation with von frey filaments and cold spray method were employed to evaluate the mechanical sensitivity and cold sensitivity of rats. Another two groups, Sham+TMP and SNI+TMP, were used to intubate the common jugular vein and implant microdialysis probes into the anterior cingulate gyrus(ACC), respectively.After intraperitoneal injection of TMP at a dose of 80 mg·kg~(-1), automatic blood collection and intracerebral microdialysis(perfusion rate of 1 µL·min~(-1)) systems were used to collect the blood and brain dialysate for 24 h. HSS T3 C_(18) reversed-phase chromatographic column(2.1 mm×50 mm, 2.5 µm) was used for liquid chromatographic separation. Gradient elution was carried out with the mobile phase of methanol-water(containing 0.005% formic acid) at a flow rate of 0.25 mL·min~(-1). Electrospray ion source was used for mass spectrometry, and the scanning mode was multi-reaction monitoring under the positive ion mode. The ion pairs for quantitative analysis were TMP m/z 137/122 and aspirin m/z 179/137, respectively. DAS 2.11 was used to calculate the pharmacokinetic parameters. The optimal time of TMP to exert the analgesia effect and inhibit cold pain sensitivity was 60 min after treatment. The TMP in the plasma and brain dialysate of SNI rats showed the T_(max) of 15 min and 30 min, the C_(max) of(2 866.43±135.39) and(1 462.14±197.38) µg·L~(-1), the AUC_(0-t) of(241 463.30±28 070.31) and(213 115.62±32 570.07) µg·min·L~(-1), the MRT_(0-t) of(353.13±47.73) and(172.16±12.72) min, and the CL_Z of 0.73 and 0.36 L·min·kg~(-1), respectively. The analgesic effect of TMP had a significant correlation with the blood drug concentration in the ACC, which indicated that this method was suitable for the detection of TMP in rat plasma and brain dialysate. The method is accurate, reliable, and sensitive and can realize the important value of the application of correlation analysis theory of "automatic blood collection-microdialysis/PK-PD" in the research on neuropathic pain.

Effect of Intraoperative infusion Magnesium Sulfate Infusion on Postoperative Quality of Recovery in Patients Undergoing Total Knee Arthroplasty: A Prospective, Double-Blind, Randomized Controlled Trial.

Background: Magnesium sulfate, an intravenous adjuvant, has recently attracted immense attention in multimodal analgesia. Previous studies confirmed the crucial role of magnesium sulfate in postoperative pain and nociceptive hypersensitivity. However, the effect of magnesium sulfate in multimodal analgesia on the quality of recovery (QoR) for elderly patients has not been thoroughly studied. Therefore, the present experiment aimed to investigate the effect of continuous intravenous magnesium sulfate on the quality of postoperative recovery in elderly patients undergoing total knee arthroplasty (TKA). Patients and Methods: In this study, a total of 148 patients scheduled to undergo unilateral total knee arthroplasty were randomized into a magnesium sulfate group (Group M, n=68) and a control group (Group C, n=66) using a double-blind, randomized controlled trial. Before induction of anesthesia, Group M received intravenous magnesium sulfate (40 mg/kg) for 15 min, followed by a continuous infusion (15 mg/kg) until the end of the procedure. In the same manner, Group C received an infusion of the same amount of isotonic saline using the same method as the Group M. Results: Compared with Group C, Group M had significantly better QoR-15 scores on postoperative day 1(POD1) than Group C (P <0.05). Analysis of the dimensions of QoR-15 scores indicated that Group M exhibited notably reduced levels of pain, and higher levels of emotional state and physical comfort than Group C (P <0.05). Furthermore, Group C had significantly higher numerical rating scale (NRS) scores at POD1 than Group M (P <0.05). Conclusion: For elderly patients undergoing knee arthroplasty, magnesium sulfate can be used as an adjuvant in a multimodal analgesic regimen to reduce early postoperative pain and improve the quality of early postoperative recovery.

Study on analgesic effect of Shentong Zhuyu Decoction in neuropathic pain rats by network pharmacology and RNA-Seq.

ETHNOPHARMACOLOGICAL RELEVANCE: Shentong Zhuyu Decoction (STZYD) is a traditional prescription for promoting the flow of Qi and Blood which is often used in the treatment of low back and leg pain clinicall with unclear mechanism. Neuropathic pain (NP) is caused by disease or injury affecting the somatosensory system. LncRNAs may play a key role in NP by regulating the expression of pain-related genes through binding mRNAs or miRNAs sponge mechanisms. AIM OF THE STUDY: To investigate the effect and potential mechanism of STZYD on neuropathic pain. METHODS: Chronic constriction injury (CCI) rats, a commonly used animal model, were used in this study. The target of STZYD in NP was analyzed by network pharmacology, and the analgesic effect of STZYD in different doses (H-STZYD, M-STZYD, L-STZYD) on CCI rats was evaluated by Mechanical withdrawal thresholds (MWT) and thermal withdrawal latency (TWL). Meanwhile, RNA-seq assay was used to detect the changed mRNAs and lncRNAs in CCI rats after STZYD intervention. GO analysis, KEGG pathway analysis, and IPA analysis were used to find key target genes and pathways, verified by qPCR and Western Blot. The regulatory effect of lncRNAs on target genes was predicted by co-expression analysis and ceRNA network construction. RESULTS: We found that STZYD can improve hyperalgesia in CCI rats, and H-STZYD has the best analgesic effect. The results of network pharmacological analysis showed that STZYD could play an analgesic role in CCI rats through the MAPK/ERK/c-FOS pathway. By mRNA-seq and lncRNA-seq, we found that STZYD could regulate the expression of Cnr1, Cacng5, Gucy1a3, Kitlg, Npy2r, and Grm8, and inhibited the phosphorylation level of ERK in the spinal cord of CCI rats. A total of 27 lncRNAs were associated with the target genes and 30 lncRNAs, 83 miRNAs and 5 mRNAs participated in the ceRNA network. CONCLUSION: STZYD has the effect of improving hyperalgesia in CCI rats through the MAPK/ERK/c-FOS pathway, which is related to the regulation of lncRNAs to Cnr1 and other key targets.

Ligustilide covalently binds to Cys703 in the pre-S1 helix of TRPA1, blocking the opening of channel and relieving pain in rats with acute soft tissue injury.

ETHNOPHARMACOLOGICAL RELEVANCE: The natural anodyne Ligustilide (Lig), derived from Angelica sinensis (Oliv.) Diels and Ligusticum chuanxiong Hort., has been traditionally employed for its analgesic properties in the treatment of dysmenorrhea and migraine, and rheumatoid arthritis pain. Despite the existing reports on the correlation between TRP channels and the analgesic effects of Lig, a comprehensive understanding of their underlying mechanisms of action remains elusive. AIM OF THE STUDY: The objective of this study is to elucidate the mechanism of action of Lig on the analgesic target TRPA1 channel. METHODS: The therapeutic effect of Lig was evaluated in a rat acute soft tissue injury model. The analgesic target was identified through competitive inhibition of TRP channel agonists at the animal level, followed by Fluo-4/Ca2+ imaging on live cells overexpressing TRP proteins. The potential target was verified through in-gel imaging, colocalization using a Lig-derived molecular probe, and a drug affinity response target stability assay. The binding site of Lig was identified through protein spectrometry and further analyzed using molecular docking, site-specific mutation, and multidisciplinary approaches. RESULTS: The administration of Lig effectively ameliorated pain and attenuated oxidative stress and inflammatory responses in rats with soft tissue injuries. Moreover, the analgesic effects of Lig were specifically attributed to TRPA1. Mechanistic studies have revealed that Lig directly activates TRPA1 by interacting with the linker domain in the pre-S1 region of TRPA1. Through metabolic transformation, 6,7-epoxyligustilide (EM-Lig) forms a covalent bond with Cys703 of TRPA1 at high concentrations and prolonged exposure time. This irreversible binding prevents endogenous electrophilic products from entering the cysteine active center of ligand-binding pocket of TRPA1, thereby inhibiting Ca2+ influx through the channel opening and ultimately relieving pain. CONCLUSIONS: Lig selectively modulates the TRPA1 channel in a bimodal manner via non-electrophilic/electrophilic metabolic conversion. The epoxidized metabolic intermediate EM-Lig exerts analgesic effects by irreversibly inhibiting the activation of TRPA1 on sensory neurons. These findings not only highlight the analgesic mechanism of Lig but also offer a novel nucleophilic attack site for the development of TRPA1 antagonists in the pre-S1 region.

Electroacupuncture promotes macrophage/microglial M2 polarization and suppresses inflammatory pain through AMPK.

Inflammatory pain, the most prevalent disease globally, remains challenging to manage. Electroacupuncture emerges as an effective therapy, yet its underlying mechanisms are not fully understood. This study investigates whether adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK)-regulated silent information regulator 1 (SIRT1) contributes to electroacupuncture's antinociceptive effects by modulating macrophage/microglial polarization in the spinal dorsal horn of a mouse model of inflammatory pain. In this study, mice, introduced to inflammatory pain through subcutaneous injections of complete freund's adjuvant (CFA) in the plantar area, underwent electroacupuncture therapy every alternate day for 30-min sessions. The assessment of mechanical allodynia and thermal hyperalgesia in these subjects was carried out using paw withdrawal frequency and paw withdrawal latency measurements, respectively. Western blot analysis measured levels of AMPK, phosphorylation-adenosine 5'-monophosphate (AMP)-activated protein kinase, SIRT1, inducible nitric oxide synthase, cluster of differentiation 86, arginase 1, and interleukin 10. In contrast to the group treated solely with CFA, the cohort receiving both CFA and electroacupuncture demonstrated notable decreases in both thermal hyperalgesia and mechanical allodynia. This was accompanied by a marked enhancement in AMPK phosphorylation levels. AMPK knockdown reversed electroacupuncture's analgesic effects and reduced M2 macrophage/microglial polarization enhancement. Additionally, AMPK knockdown significantly weakened electroacupuncture-induced SIRT1 upregulation, and EX-527 injection attenuated electroacupuncture's facilitation of M2 macrophage/microglial polarization without affecting AMPK phosphorylation levels. Furthermore, combining electroacupuncture with SRT1720 enhanced the analgesic effect of SRT1720. Our findings suggest that AMPK regulation of SIRT1 plays a critical role in electroacupuncture's antinociceptive effect through the promotion of M2 macrophage/microglial polarization.

Synthesis of Ottonia anisum Extract Mediated ZnO NPs and Their Local Anesthetic, Analgesic and HCl­induced Acute Lung Injury Activities.

In this study, we outlined the green synthesis of Zinc oxide nanoparticles (ZnO NPs) using the plant-mediated method. Employing the nitrate derivative of Zinc and the extract from the native medicinal plant, Ottonia anisum, the nanoparticles were effectively produced. After obtaining a yellow-colored paste, it was meticulously dried, gathered, and set aside for subsequent examination. The UV-visible spectrometry analysis indicated an absorption peak at 320 nm, which is indicative of ZnO NPs. Characterization techniques, such as XRD and HR-TEM, confirmed the existence of agglomerated ZnO NPs with an average diameter of 40 nm. Through EDS analysis, distinct energy signals for both Zinc and Oxygen were observed, confirming their composition. Furthermore, FT-IR spectroscopy highlighted an absorption peak for Zn-O bonding in the range of 400 to 600 cm -1 . Further, we employed three distinct pain models in mice to evaluate the influence of ZnO NPs on the nociceptive threshold. Our findings revealed that, when orally administered, ZnO NPs at concentrations ranging from 5-20 mg/kg exerted a dose-dependent analgesic effect in both the hot-plate and the acetic acid-induced writhing tests. Moreover, when ZnO NPs were administered at doses between 2.5-10 mg/kg, there was a notable reduction in pain responses during both the initial and subsequent phases of the formalin test, but no change in PGE 2 production within the mice's hind paw was found. On the other hand, acute lung injury studies revealed that the administration of ZnO NPs orally 90 minutes prior to HCl instillation decreased the neutrophil infiltration into the lungs in a doseresponsive manner. This reduction in pulmonary inflammation was paralleled by a significant decrease in lung edema, as evidenced by the reduced total protein content in the BALF. Additionally, the ZnO NPs appeared to recalibrate the lung's redox equilibrium following HCl exposure, which was determined through measurements of ROS, malondialdehyde, glutathione, and catalase activity. All these results further indicated the potential of biofabricated ZnO NPs for future applications in analgesics and acute lung injury treatments.

Electroacupuncture suppresses neuronal ferroptosis to relieve chronic neuropathic pain.

Growing evidence supports the analgesic efficacy of electroacupuncture (EA) in managing chronic neuropathic pain (NP) in both patients and NP models induced by peripheral nerve injury. However, the underlying mechanisms remain incompletely understood. Ferroptosis, a novel form of programmed cell death, has been found to be activated during NP development, while EA has shown potential in promoting neurological recovery following acute cerebral injury by targeting ferroptosis. In this study, to investigate the detailed mechanism underlying EA intervention on NP, male Sprague-Dawley rats with chronic constriction injury (CCI)-induced NP model received EA treatment at acupoints ST36 and GV20 for 14 days. Results demonstrated that EA effectively attenuated CCI-induced pain hypersensitivity and mitigated neuron damage and loss in the spinal cord of NP rats. Moreover, EA reversed the oxidative stress-mediated spinal ferroptosis phenotype by upregulating reduced expression of xCT, glutathione peroxidase 4 (GPX4), ferritin heavy chain (FTH1) and superoxide dismutase (SOD) levels, and downregulating increased expression of acyl-CoA synthetase long-chain family member 4 (ACSL4), malondialdehyde levels and iron overload. Furthermore, EA increased the immunofluorescence co-staining of GPX4 in neurons cells of the spinal cord of CCI rats. Mechanistic analysis unveiled that the inhibition of antioxidant pathway of Nrf2 signalling via its specific inhibitor, ML385, significantly countered EA's protective effect against neuronal ferroptosis in NP rats while marginally diminishing its analgesic effect. These findings suggest that EA treatment at acupoints ST36 and GV20 may protect against NP by inhibiting neuronal ferroptosis in the spinal cord, partially through the activation of Nrf2 signalling.

Phytochemical, Pharmacological, and Molecular Docking Study of Dry Extracts of Matricaria discoidea DC. with Analgesic and Soporific Activities.

Pineapple weed (Matricaria discoidea DC.) is a widespread plant in Europe and North America. In ethnomedicine, it is well-known for its anti-inflammatory and spasmolytic activities. The aim of this research was to develop novel methods of M. discoidea processing to obtain essential oil and dry extracts and to investigate their phytochemical compositions. Moreover, the molecular docking of the main substances and the in vivo studies on their soporific and analgesic activities were conducted. The essential oil and two dry extracts from M. discoidea were prepared. A total of 16 phenolic compounds (seven flavonoids, seven hydroxycinnamic acids, and two phenolic acids) in the dry extracts were identified by means of UPLC-MS/MS. In the essential oil, nine main terpenoids were identified by gas chromatography (GC). It was shown that phenolic extraction from the herb was successful when using 70% ethanol in a triple extraction method and at a ratio of 1:14-1:16. The in vivo studies with rodents demonstrated the analgesic activity of the M. discoidea extracts and improvements in the sleep of animals. The dry extracts of M. discoidea did not show any toxicity. The molecular docking analysis showed a high probability of COX-1,2 inhibition and NMDA receptor antagonism by the extracts.

Chemical composition and potential antioxidant, anti-inflammatory, and analgesic efficacy of Cistus albidus L.

This study aims to assess the chemical composition of the aqueous extract of Cistus albidus L. leaves, as well as the potential of aqueous and hydroethanol extracts of the leaves and seeds as analgesic, anti--inflammatory, and antioxidant agents. The contents of phenolics and inorganic constituents were determined in C. albidus seeds and leaves; antioxidant capacity was assessed by 3 complementary and diverse tests. The carrageenan-induced paw edema technique was used to investigate the anti-inflammatory effect in vivo, and albumin denaturation to evaluate the anti-inflammatory effect in vitro. The acetic acid-induced contortion test, the tail-flick test, and the plantar test were used to assess the analgesic effi cacy in vivo. Chemical analysis was performed by UPLC-MS/MS to quantify several phenolic compounds including catechin (1,627.6 mg kg-1), quercitrin (1,235.8 mg kg-1) and gallic acid (628. 2 mg kg-1). The ICP analysis revealed that potassium and calcium were the main inorganic components in the seeds and leaves of C. albidus. The hydroethanolic extract of the leaves showed the highest content of polyphenols/flavonoids, whereas the highest value of proantho cyanidins was detected in the aqueous extract of the seeds. All extracts showed potent antioxidant activity related to different phenolic compounds (quercetin, gallic acid, astragalin, catechin, and rutin). The aqueous extract of the leaves strongly inhibited paw edema (76.1 %) after 6 h of treatment and showed maximal inhibition of protein denaturation (191.0 µg mL-1 for 50 % inhibition) and analgesic activity in different nociceptive models. The presented data reveal that C. albidus extracts potentially show antioxidant, anti-inflammatory, and analgesic activities that could confirm the traditional use of this plant.

Chemical composition, antioxidant, antimicrobial, and wound healing effects of Trachyspermum roxburghianum (DC.) H. Wolff essential oil: An in vivo and in silico approach.

ETHNOPHARMACOLOGICAL RELEVANCE: Trachyspermum roxburghianum (DC.) H. Wolff, commonly known as 'Ajamoda,' is a neglected Indian spice highly used in Ayurveda and folklore remedies as an antimicrobial for chronic wounds and discharges, along with many other disease conditions. AIM OF THE STUDY: The objective of the study was to explore chemical composition and to investigate the antioxidant, antimicrobial, analgesic, and wound healing activities of T. roxburghianum fruit essential oil from India. MATERIALS AND METHODS: The phytochemical characterization of the oil was determined through standard qualitative procedures and the gas chromatography-mass spectrometry (GC-MS) technique. The in vitro antioxidant aptitude was assessed by scavenging DPPH and ABTS radicals. The antimicrobial potential of the oil was investigated using the disc diffusion method, followed by the determination of minimum inhibitory concentration against Gram-positive and Gram-negative bacterial and fungal strains. The analgesic potential was evaluated using thermal and chemically induced pain models in Swiss albino mice. Wound healing was assessed in vivo, including determining wound contraction rates, histopathology, and hydroxyproline estimation, using the excision wound model in Swiss albino mice. RESULTS: GC-MS analysis identified 55 compounds with major terpenoids, including thymol (13.8%), limonene (11.5%), and others. Substantial radical-scavenging activity was exhibited by T. roxburghianum fruit essential oil (TREO) (IC50 94.41 ± 2.00 µg/mL in DPPH assay and 91.28 ± 1.94 µg/mL in ABTS assay). Microorganisms were inhibited with low MIC (2 µL/mL for the inhibition of Staphylococcus aureus and Bacillus subtilis; 4 µL/mL against Salmonella typhi and 16 µL/mL against Candida albicans). In the cytotoxicity study, no cytotoxicity was observed on the Monkey Normal Kidney Cell line (Vero). Significant antinociceptive effects were observed (25.47 ± 1.10 % of inhibition at 100 mg/kg and 44.31 ± 1.69 % at 200 mg/kg). A remarkable rate of wound closure and epithelization, along with a marked increase in hydroxyproline content, were observed for the oil during wound healing in mice. CONCLUSIONS: The results suggested that oil could be utilized as a potential source of wound healing therapeutics.

Electroacupuncture attenuates nociceptive behaviors in a mouse model of cancer pain.

Pain is a major symptom in cancer patients, and cancer-induced bone pain (CIBP) is the most common type of moderate and severe cancer-related pain. The current available analgesic treatments for CIBP have adverse effects as well as limited therapeutic effects. Acupuncture is proved effective in pain management as a safe alternative therapy. We evaluated the analgesic effect of acupuncture in treatment of cancer pain and try to explore the underlying analgesic mechanisms. Nude mice were inoculated with cancer cells into the left distal femur to establish cancer pain model. Electroacupuncture (EA) treatment was applied for the xenograft animals. Pain behaviors of mice were evaluated, followed by the detections of neuropeptide-related and inflammation-related indicators in peripheral and central levels. EA treatment alleviated cancer-induced pain behaviors covering mechanical allodynia, thermal hyperalgesia and spontaneous pain, and also down-regulated immunofluorescence expressions of neuropeptide CGRP and p75 in the skin of affected plantar area in xenograft mice, and inhibited expressions of overexpressed neuropeptide-related and inflammation-related protein in the lumbar spinal cord of xenograft mice. Overall, our findings suggest that EA treatment ameliorated cancer-induced pain behaviors in the mouse xenograft model of cancer pain, possibly through inhibiting the expressions of neuropeptide-related and inflammation-related protein in central level following tumor cell xenografts.

Role of noradrenergic and dopaminergic systems in the antinociceptive effect of N-(3-(phenylselanyl)prop-2-yn-1-yl)benzamide in mice.

Pain has a negative impact on public health, reducing quality of life. Unfortunately, current treatments are not fully effective and have adverse effects. Therefore, there is a need to develop new analgesic compounds. Due to promising results regarding the antinociceptive effect of N-(3-(phenylselanyl)prop-2-in-1-yl)benzamide (SePB), this study aimed to evaluate the participation of the dopaminergic and noradrenergic systems in this effect in mice, as well as its toxicity. To this, the antagonists sulpiride (D2/D3 receptor antagonist, 5 mg/kg), SCH-23390 (D1 receptor antagonist, 0.05 mg/kg), prazosin (α1 adrenergic receptor antagonist, 0.15 mg/kg), yohimbine (α2-adrenergic receptors, 0.15 mg/kg) and propranolol (non-selective ß-adrenergic antagonist, 10 mg/kg) were administered intraperitoneally to mice 15 min before SePB (10 mg/kg, intragastrically), except for propranolol (20 min). After 26 min of SePB administration, the open field test was performed for 4 min to assess locomotor activity, followed by the tail immersion test to measure the nociceptive response. For the toxicity test, animals received a high dose of 300 mg/kg of SePB. SePB showed an increase in the latency for nociceptive response in the tail immersion test, and this effect was prevented by SCH-23390, yohimbine and propranolol, indicating the involvement of D1, α2 and ß-adrenergic receptors in the antinociceptive mechanism of the SePB effect. No changes were observed in the open field test, and the toxicity assessment suggested that SePB has low potential to induce toxicity. These findings contribute to understanding SePB's mechanism of action, with a focus on the development of new alternatives for pain treatment.

Study on the quality of Corydalis Rhizoma in Zhejiang based on multidimensional evaluation method.

ETHNOPHARMACOLOGICAL RELEVANCE: The quality requirements of Corydalis Rhizoma (CR) in different producing areas are uniform, resulting in uneven efficacy. As a genuine producing area, the effective quality control of CR in Zhejiang Province (ZJ) could provide a theoretical basis for the rational application of medicinal materials. AIM OF THE STUDY: The purpose of this study was to effectively distinguish the CR inside and outside ZJ, and provided a theoretical basis for the quality control and material basis research of ZJ CR. MATERIALS AND METHODS: The core components of ZJ CR could be identified by HPLC combined with chemometrics screening, and the quality of CR from different producing areas was evaluated by a genetic algorithm-back propagation (GA-BP) neural network. Chromaticity and near-infrared (NIR) spectroscopy were used to identify CR inside and outside ZJ, and rapid content prediction was realized. The analgesic effect of CR in different regions was compared by a zebrafish analgesic experiment. Analgesic experiments in rats and analysis of the research status of quality components were used to screen the quality control components of ZJ CR. RESULTS: The contents of palmatine hydrochloride (YSBMT), dehydrocorydaline (TQZJJ), tetrahydropalmatine (YHSYS), tetrahydroberberine (SQXBJ), corydaline (YHSJS), stylopine (SQHLJ), and isoimperatorin (YOQHS) in ZJ CR were higher than those in CR from outside ZJ, but the content of protopine (YAPJ) and berberine hydrochloride (YSXBJ) was lower than that in CR from outside ZJ. YHSJS and SQHLJ could be used as the core components to identify ZJ CR. The GA-BP neural network showed that the relative importance of ZJ CR was the strongest. Chroma-content correlation analysis and the NIR qualitative model could effectively distinguish CR from inside and outside of ZJ, and the NIR quantitative model could quickly predict the content of CR from inside and outside of ZJ. Zebrafish experiments showed that ZJ, Shaanxi (SX), Henan (HN), and Sichuan (SC) CR had significant analgesic effects, while Hebei (HB) CR had no significant analgesic effect. Overall comparison, the analgesic effect of ZJ CR was better than that of CR outside ZJ. The comprehensive score of the grey correlation degree between YAPJ, YSBMT, YSXBJ, TQZJJ, YHSYS, YHSJS, SQXBJ, and SQHLJ were higher than 0.9, and the research frequency were extremely high. CONCLUSIONS: The relative importance of the content and origin of most components of ZJ CR was higher than that of CR outside ZJ. The holistic analgesic effect of ZJ CR was better than that of CR outside ZJ, but slightly lower than that of SX CR. YHSJS and SQHLJ could be used as the core components to identify ZJ CR. YAPJ, YSBMT, YSXBJ, TQZJJ, YHSYS, SQXBJ, YHSJS, and SQHLJ could be used as the quality control components of ZJ CR. The multidimensional evaluation method used in this study provided a reference for the quality control and material basis research of ZJ CR.

The value of local dexmedetomidine as an adjuvant to ultrasound-guided wide awake local anesthesia no tourniquet (WALANT) in flexor tendon repair surgeries: a randomized controlled trial.

BACKGROUND: The Wide-Awake Local Anesthesia No Tourniquet (WALANT) technique allows intraoperative motor assessment of tendon repair integrity of the hand compared with general anesthesia or brachial plexus block. No studies have tested the effect of adding dexmedetomidine to lidocaine on the analgesic properties of the WALANT technique, which is the aim of our study. METHODS: A total of 128 patients aged more than 18 years were scheduled for surgical flexor tendon injury repair using WALANT technique. Patients were divided into two equal groups. Ultrasound-guided subcutaneous injection of lidocaine 1% with dexmedetomidine (1 µg/kg), Group D, or without dexmedetomidine, Group C, was performed at four points: proximal to the wrist joint, the distal forearm, palm region, and proximal phalanges. The primary outcome was total morphine consumption throughout the first postoperative day. Secondary outcomes included number of patients requiring rescue analgesia, time to first analgesic request, and pain score. RESULTS: Total morphine consumption was significantly (P < 0.001) lower in group D (2.66 ± 0.998) than in group C (3.66 ± 1.144) mg. Number of patients requiring rescue analgesia was significantly (P < 0.001) lower in group D (54.7% (35)) than group C (100.0% (64)). The time for first request for analgesia was significantly (P < 0.001) longer in group D (11.31 ± 6.944) than in group C (5.91 ± 4.839) h. Pain score was significantly higher in group C than D at three (P < 0.001), and six (P = 0.001) hours (P = 0.001) postoperatively. CONCLUSION: Dexmedetomidine significantly improves the analgesic quality of WALANT when added to lidocaine with less opioid consumption. TRIAL REGISTRATION: (ID: PACTR202203906027106; Date: 31/07/2023).

Antinociceptive and anti-inflammatory activity of extracts and α-pyrones isolated from Cantinoa stricta.

This study evaluated the composition and the antinociceptive and anti-inflammatory activity of the crude extracts and two isolated compounds, anamarine (ANA) and 10-epi-olguine (eOL), obtained from the leaves of Cantinoa stricta (Lamiaceae). Crude ethanolic extract (EEt) and dichloromethane extract (DCM), selected based on NMR data, were submitted to pharmacological tests in male Swiss mice. The oral administration of EEt and DCM significantly reduced the second phase of formalin-induced nociception (60%), lipopolysaccharide (LPS)-induced mechanical hyperalgesia (90%), and carrageenan (Cg)-induced edema (25%). ANA and eOL, the major compounds in EEt and DCM extracts, administered orally or locally (in the paw), also reduced the LPS-induced mechanical hyperalgesia (Oral ID50 1.9 and 3.9 mg/kg; Local ID50 93.4 and 677.3 ng, respectively) without changing the thermal acute nociception or the motor performance of the animals. Local administration of ANA and eOL also reduced Cg-induced edema (40 and 23%, respectively). These isolated compounds did not change the mechanical hyperalgesia induced by tumor necrosis factor-α, interleukin-1ß, prostaglandin E2, dibutyryl cyclic AMP, or forskolin but reversed the hyperalgesia induced by dopamine, epinephrine, and phorbol 12-myristate 13-acetate. The hyperalgesia induced by epinephrine was reversed in male but not in female mice, in which this response is not dependent on protein kinase C (PKC). These results suggest that C. stricta extracts possess antinociceptive and anti-inflammatory activity which is related to the presence of ANA and eOL. Differently from the known analgesics, these substances seem to exert their action mainly interfering with the sympathetic component of pain, possibly with PKC.

A comprehensive review of Pfaffia glomerata botany, ethnopharmacology, phytochemistry, biological activities, and biotechnology.

ETHNOPHARMACOLOGICAL RELEVANCE: Pfaffia glomerata (Spreng.) Pedersen, Amaranthaceae, is found in South America, mainly in Brazil, where it is considered a species of great medicinal interest owing to its popular use as a tonic, aphrodisiac, anti-inflammatory, and analgesic. These properties can be attributed to the presence of the phytosteroid, 20-Hydroxyecdysone (ß-ecdysone), the main compound found in its roots. AIM OF THE REVIEW: This review aims to provide information about the botanical characteristics, ethnomedicinal uses, the phytochemistry, the biological activities, and the biotechnology of P. glomerata, an important species to local communities and groups researching medicinal plants of South America. MATERIALS AND METHODS: The information available on P. glomerata was collected from scientific databases (ScienceDirect, PubMed/MEDLINE, SciELO, and Scopus) until June 7, 2023, using the search terms "Pfaffia glomerata", "Pfaffia glomerata (Spreng.) Pedersen", and "Brazilian ginseng". The review includes studies that evaluated the botanical, ethnopharmacological, and phytochemical aspects, biological properties, nutraceutical uses, and the application of biotechnology for improving the biosynthesis of metabolites of interest. RESULTS: A total of 207 studies were identified, with 81 articles read in full. Seventy-six studies were included for qualitative synthesis. Overall, 40 compounds belonging to different classes are presented in this review, including ecdysteroids, triterpenes, saponins, flavonoids, anthraquinones, tannins, coumarins, alkaloids, and polysaccharides. Among them, flavonoids, anthraquinones, tannins, coumarins, and alkaloids were only putatively identified. ß-Ecdysone, triterpenes, saponins, and polysaccharides are the chemical components most frequently identified and isolated from P. glomerata and possibly responsible for ethnopharmacological use and the biological activities of this species, with important in vitro and in vivo activities, such as anti-inflammatory, antidepressant, aphrodisiac, analgesic, gastroprotective, antioxidant, and prebiotic. CONCLUSIONS: This review summarizes discussions about the P. glomerata species, highlighting its ethnopharmacological, chemical, biotechnological, and nutraceutical importance. New scientific studies on this species are encouraged in the search for new therapeutic molecules with pharmaceutical potential and nutraceutical applications.

Schisandrin B from Schisandra chinensis alleviated pain via glycine receptors, Nav1.7 channels and Cav2.2 channels.

ETHNOPHARMACOLOGICAL RELEVANCE: Schisandra chinensis, the dried and ripe fruit of the magnolia family plant Schisandra chinensis (Turcz.) Baill, was commonly used in traditional analgesic prescription. Studies have shown that the extract of Schisandra chinensis (SC) displayed analgesic activity. However, the analgesic active component and the exact mechanisms have yet to be revealed. AIM OF THE STUDY: The present study was to investigate the anti-nociceptive constituent of Schisandra chinensis, assess its analgesic effect, and explore the potential molecular mechanisms. MATERIALS AND METHODS: The effects of a series of well-recognized compounds from SC on glycine receptors were investigated. The analgesic effect of the identified compound was evaluated in three pain models. Mechanistic studies were performed using patch clamp technique on various targets expressed in recombinant cells. These targets included glycine receptors, Nav1.7 sodium channels, Cav2.2 calcium channels et al. Meanwhile, primary cultured spinal dorsal horn (SDH) neurons and dorsal root ganglion (DRG) neurons were also utilized. RESULTS: Schisandrin B (SchB) was a positive allosteric modulator of glycine receptors in spinal dorsal horn neurons. The EC50 of SchB on glycine receptors in spinal dorsal horn neurons was 2.94 ± 0.28 µM. In three pain models, the analgesic effect of SchB was comparable to that of indomethacin at the same dose. Besides, SchB rescued PGE2-induced suppression of α3 GlyR activity and alleviated persistent pain. Notably, SchB could also potently decrease the frequency of action potentials and inhibit sodium and calcium channels in DRG neurons. Consistent with the data from DRG neurons, SchB was also found to significantly block Nav1.7 sodium channels and Cav2.2 channels in recombinant cells. CONCLUSION: Our results demonstrated that, Schisandrin B, the primary lignan component of Schisandra chinensis, may exert its analgesic effect by acting on multiple ion channels, including glycine receptors, Nav1.7 channels, and Cav2.2 channels.

8-shogaol derived from dietary ginger alleviated acute and inflammatory pain by targeting TRPV1.

Ginger, a well-known spice plant, has been used widely in medicinal preparations for pain relief. However, little is known about its analgesic components and the underlying mechanism. Here, we ascertained, the efficacy of ginger ingredient 8-Shogaol (8S), on inflammatory pain and tolerance induced by morphine, and probed the role of TRPV1 in its analgesic action using genetic and electrophysiology approaches. Results showed that 8S effectively reduced nociceptive behaviors of mice elicited by chemical stimuli, noxious heat as well as inflammation, and antagonized morphine analgesic tolerance independent on opioid receptor function. Genetic deletion of TRPV1 significantly abolished 8S' analgesia action. Further calcium imaging and patch-clamp recording showed that 8S could specifically activate TRPV1 in TRPV1-expressing HEK293T cells and dorsal root ganglion (DRG) neurons. The increase of [Ca2+]i in DRG was primarily mediated through TRPV1. Mutational and computation studies revealed the key binding sites for the interactions between 8S and TRPV1 included Leu515, Leu670, Ile573, Phe587, Tyr511, and Phe591. Further studies showed that TRPV1 activation evoked by 8S resulted in channel desensitization both in vitro and in vivo, as may be attributed to TRPV1 degradation or TRPV1 withdrawal from the cell surface. Collectively, this work provides the first evidence for the attractive analgesia of 8S in inflammatory pain and morphine analgesic tolerance mediated by targeting pain-sensing TRPV1 channel. 8S from dietary ginger has potential as a candidate drug for the treatment of inflammatory pain.

NTPDase1-ATP-P2Y2Rs axis in the sciatic nerve contributes to acupuncture at "Zusanli" (ST36)-induced analgesia in ankle arthritis rats.

BACKGROUND: The efficacy of acupuncture at Zusanli (ST36) in alleviating lower-limb pain is widely acknowledged in clinical practice, while its underlying mechanism remains incompletely elucidated. Our previous research had revealed that the prompt analgesia induced by needling-ST36 was accompanied by expression alterations in certain exco-nucleotidases within the sciatic nerve. Building upon this finding, the current work focused on NTPDase1, the primary ecto-nucleotidase in the human body, which converts ATP into AMP. METHODS: A 20-min acupuncture was administered unilaterally at the ST36 on rats with acute ankle arthritis. The pain thresholds of the injured hind paws were determined. Pharmacological interference was carried out by introducing the corresponding reagents to the sciatic nerve. ATP levels around the excised nerve were measured using a luciferase-luciferin assay. Live calcium imaging, utilizing the Fura 2-related-F340/F380 ratio, was conducted on Schwann cells in excised nerves and cultured rat SCs line, RSC96 cells. RESULTS: The analgesic effect induced by needling-ST36 was impaired when preventing ATP degradation via inhibiting NTPDase1 activities with ARL67156 or Ticlopidine. Conversely, increasing NTPDase1 activities with Apyrase duplicated the acupuncture effect. Similarly, preventing the conversion of AMP to adenosine via suppression of NT5E with AMP-CP hindered the acupuncture effect. Unexpectedly, impeded ATP hydrolysis ability and diminished NTPDase1 expression were observed in the treated group. Agonism at P2Y2Rs with ATP, UTP, or INS365 resulted in anti-nociception. Contrarily, antagonism at P2Y2Rs with Suramin or AR-C 118925xx prevented acupuncture analgesia. Immunofluorescent labeling demonstrated that the treated rats expressed more P2Y2Rs that were predominant in Schwann cells. Suppression of Schwann cells by inhibiting ErbB receptors also prevented acupuncture analgesia. Finally, living imaging on the excised nerves or RSC96 cells showed that agonism at P2Y2Rs indeed led to [Ca2+]i rise. CONCLUSION: These findings strongly suggest that the analgesic mechanism of needling-ST36 on the hypersensation in the lower limb partially relies on NTPDase1 activities in the sciatic nerve. In addition to facilitating adenosine signaling in conjunction with NT5E, most importantly, NTPDase1 may provide an appropriate low-level ATP milieu for the activation of P2Y2R in the sciatic nerve, particularly in Schwann cells.