Antinociceptive Effect of Cyperi rhizoma and Corydalis tuber Extracts on Neuropathic Pain in Rats

Real-world observations and impacts of Chinese herbal medicine for migraine: results of a registry-based cohort study

Background: Migraine is a prevalent, recurrent condition with substantial disease burden. Chinese herbal medicine (CHM) has been used frequently for migraine in controlled clinical settings. This study is to summarise the characteristics of patients who seek clinical care in a tertiary Chinese medicine hospital in China; to gather their preferences and values of using CHM; to explore the effect of CHM for migraine and its comorbidities in a real-world setting, and to collect first-hand expertise of clinicians' practice pattern in prescribing CHM for migraine. Methods: This registry-based cohort study was prospectively conducted at Guangdong Provincial Hospital of Chinese Medicine from December 2020 to May 2022. Adult migraine patients seeking their initial anti-migraine clinical care at the hospital were consecutively recruited and followed up for 12 weeks. Practitioners specialised in headache management prescribed individualised treatments without research interference. Standardised case report forms were employed to gather information on patients' preferences and perspective of seeking clinical care, as well as to assess participants' migraine severity, comorbidities, and quality of life, at 4-weeks intervals. Various analytical methods were utilised based on the computed data. Results: In this study, we observed 248 participants. Of these, 73 received CHM treatment for 28 days or longer. Notably, these participants exhibited a greater disease severity, compared to those treated with CHM for less than 28 days. Of the 248 participants, 83.47% of them expected CHM would effectively reduce the severity of their migraine, around 50% expected effects for migraine-associated comorbidities, while 51.61% expressing concerns about potential side effects. CHM appeared to be effective in reducing monthly migraine days and pain intensity, improving patients' quality of life, and potentially reducing comorbid anxiety, with a minimum of 28 days CHM treatment. Herbs such as gan cao, gui zhi, chuan xiong, fu ling, bai zhu, yan hu suo, etc. were frequently prescribed for migraine, based on patients' specific symptoms. Conclusion: CHM appeared to be beneficial for migraine and comorbid anxiety in real-world clinical practice when used continuously for 28 days or more. Clinical Trial Registration: clinicaltrials.gov, identifier ChiCTR2000041003.

Based on spinal central sensitization creating analgesic screening approach to excavate anti-neuropathic pain ingredients of Corydalis yanhusuo W.T.Wang

ETHNOPHARMACOLOGICAL RELEVANCE

Corydalis Rhizome (RC) as a traditional analgesic Chinese medicine is the dried tuber of Corydalis yanhusuo W.T.Wang. Many efforts have revealed that RC could effectively alleviate neuropathic pain, while its active ingredients in neuropathic pain are still not clear.

AIM OF THE STUDY

Spinal central sensitization contributes greatly to neuropathic pain, and neuron, astrocyte and microglia play important roles in spinal central sensitization. The aim of the present study is to excavate active compounds in RC regulating spinal central sensitization to inhibit neuropathic pain.

MATERIALS AND METHODS

Immunofluorescence and western blotting were used to determine protein expression levels. Gene expression levels were detected by RT-PCR. PC12 neuronal cells, C6 astrocyte cells, and BV2 microglia cells were cultured for in vitro studies. Targeting multi types of cells extraction combined with HPLC-Q-TOF-MS/MS was established to identify components binding to above cells. Animal studies were used to verify the analgesic activities of components.

RESULTS

Total alkaloids of RC (RC-TA) significantly relieved neuropathic pain in chronic constriction injury (CCI) rats and repressed spinal central sensitization. Eight components of RC-TA were found to bind to PC12, C6, or BV2 cells. They could respectively suppress the activation of cells in vitro and alleviate CCI-induced neuropathic pain, among which glaucine and dehydrocorydaline induced antinociception was stronger than l-THP. Meanwhile, glaucine had no effect on acute or chronic inflammatory pain, and its antinociception in neuropathic pain could be abolished by dopamine D1 receptor agonist.

CONCLUSIONS

Employing multi types of cells based on spinal central sensitization rather than single cell may allow for more thorough excavation of active substances. Glaucine was firstly found could attenuate neuropathic pain but not other types of pain which indicated that different alkaloids in RC exert distinct analgesic effects on different pain models, and gluacine has the potential to be developed as an analgesic drug specifically for neuropathic pain relieving.

Study on the quality difference of Cyperus rotundus before and after vinegar processing based on ultra-high-performance liquid chromatography-quadrupole-time of flight-mass spectrometry and molecular network combined with color parameters

Cyperus rotundus is the dry rhizome of the Cyperaceae plant Cyperus. Although there are two types of processed products in clinics, their quality differences are not clear, and the identification methods are more complex. In this study, the chemical composition of different processed products of Cyperus rotundus was characterized using ultra-high-performance liquid chromatography-quadrupole-time of flight-mass spectrometry and molecular network analysis, to identify the potential chemical markers and to establish a quick and simple color-based discrimination method. Among the 65 compounds analyzed, 12 showed significant differences. Observing the color, the surface brightness (L*) of Cyperus rotundus decreased after vinegar processing, while red (a*) and yellow (b*) values increased. These color values correlated significantly with chemical compositions. Finally, a color discriminant function was established and verified for raw Cyperus rotundus and vinegar-processing Cyperus rotundus. Based on this study, Cyperus rotundus' quality can be effectively controlled and provides a method for the comprehensive characterization of chemical components and chemical markers of other traditional Chinese medicine and processed products, as well as new ideas and methods in identification and quality evaluation.

Inhibition of Spinal TRPV1 Reduces NMDA Receptor 2B Phosphorylation and Produces Anti-Nociceptive Effects in Mice with Inflammatory Pain

Transient receptor potential vanilloid 1 (TRPV1) has been implicated in peripheral inflammation and is a mediator of the inflammatory response to various noxious stimuli. However, the interaction between TRPV1 and N-methyl-D-aspartate (NMDA) receptors in the regulation of inflammatory pain remains poorly understood. This study aimed to investigate the analgesic effects of intrathecal administration of capsazepine, a TRPV1 antagonist, on carrageenan-induced inflammatory pain in mice and to identify its interactions with NMDA receptors. Inflammatory pain was induced by intraplantar injection of 2% carrageenan in male ICR mice. To investigate the analgesic effects of capsazepine, pain-related behaviors were evaluated using von Frey filaments and a thermal stimulator placed on the hind paw. TRPV1 expression and NMDA receptor phosphorylation in the spinal cord and glutamate concentration in the spinal cord and serum were measured. Intrathecal treatment with capsazepine significantly attenuated carrageenan-induced mechanical allodynia and thermal hyperalgesia. Moreover, carrageenan-enhanced glutamate and phosphorylation of NMDA receptor subunit 2B in the spinal cord were suppressed by capsazepine administration. These results indicate that TRPV1 and NMDA receptors in the spinal cord are associated with inflammatory pain transmission, and inhibition of TRPV1 may reduce inflammatory pain via NMDA receptors.

Uncovering Modern Clinical Applications of Fuzi and Fuzi-Based Formulas: A Nationwide Descriptive Study With Market Basket Analysis

Background: As time evolved, traditional Chinese medicine (TCM) became integrated into the global medical system as complementary treatments. Some essential TCM herbs started to play a limited role in clinical practices because of Western medication development. For example, Fuzi (Aconiti Lateralis Radix Praeparata) is a toxic but indispensable TCM herb. Fuzi was mainly used in poor circulation and life-threatening conditions by history records. However, with various Western medication options for treating critical conditions currently, how is Fuzi used clinically and its indications in modern TCM are unclear. This study aimed to evaluate Fuzi and Fuzi-based formulas in modern clinical practices using artificial intelligence and data mining methods. Methods: This nationwide descriptive study with market basket analysis used a cohort selected from the Taiwan National Health Insurance database that contained one million national representatives between 2003 and 2010 used for our analysis. Descriptive statistics were performed to demonstrate the modern clinical indications of Fuzi. Market basket analysis was calculated by the Apriori algorithm to discover the association rules between Fuzi and other TCM herbs. Results: A total of 104,281 patients using 405,837 prescriptions of Fuzi and Fuzi-based formulas were identified. TCM doctors were found to use Fuzi in pulmonary (21.5%), gastrointestinal (17.3%), and rheumatologic (11.0%) diseases, but not commonly in cardiovascular diseases (7.4%). Long-term users of Fuzi and Fuzi-based formulas often had the following comorbidities diagnosed by Western doctors: osteoarthritis (31.0%), peptic ulcers (29.5%), hypertension (19.9%), and COPD (19.7%). Patients also used concurrent medications such as H2-receptor antagonists, nonsteroidal anti-inflammatory drugs, β-blockers, calcium channel blockers, and aspirin. Through market basket analysis, for the first time, we noticed many practical Fuzi-related herbal pairs such as Fuzi-Hsihsin (Asari Radix et Rhizoma)-Dahuang (Rhei Radix et Rhizoma) for neurologic diseases and headache. Conclusion: For the first time, big data analysis was applied to uncover the modern clinical indications of Fuzi in addition to traditional use. We provided necessary evidence on the scientific use of Fuzi in current TCM practices, and the Fuzi-related herbal pairs discovered in this study are helpful to the development of new botanical drugs.

Efficacy and safety of the classic Chinese herbal prescription Sanpian decoction on migraine: A meta-analysis

OBJECTIVES

To evaluate the efficacy and safety of the classic Chinese herbal prescription Sanpian decoction for curing migraine.

METHODS

Scopus, PubMed, EMBASE, SPRINGER LINK, China National Knowledge Infrastructure (CNKI), Weipu Database and WanFang Database were searched from inception through January 2019 to identify randomized controlled trials (RCTs) that evaluated the efficacy and safety of Sanpian decoction.

RESULTS

Fifteen RCTs with a total of 1377 participants were identified. Compared with the control drugs, Sanpian decoction and Sanpian decoction combined with Sibelium significantly improved the clinical efficacy separately (relative risk [RR] 4.19, 95% confidence intervals [CI] 2.91 to 6.04, P < 0.00001; RR 1.29, 95% CI 1.09 to 1.54, P = 0.003 separately); the Sanpian decoction significantly improved the visual analogue scale score (VAS) (mean differences [MD] -1.83, 95% CI -2.69 to -0.97, P < 0.0001), headache score (MD -3.77, 95% CI -7.20 to -0.34, P = 0.03) and reduced the frequency of headache attacks (MD -1.61, 95% CI -2.07 to -1.14, P < 0.00001) and the concentration of endothelin (ET) (MD -11.90, 95% CI -23.22 to -0.58, P = 0.04) when compared with control drugs. There were minor side effects related to Sanpian decoction which were well tolerated.

CONCLUSIONS

Sanpian decoction is of significant benefits and relative safety in treating migraine. However, more rigorous studies with larger sample sizes are needed due to methodological flaws and low quality of the included trials in this meta-analysis.

A thirteen-week oral toxicity study of So-ochim-tang-gami-bang, a traditional Korean medicine, in Sprague-Dawley rats

ETHNOPHARMACOLOGICAL RELEVANCE

So-ochim-tang-gamibang (SOCG) is a traditional Korean medicine formulated to control internal energy flow (Qi) and has been prescribed to improve stress-induced depressive disorders.

AIM OF THE STUDY

SOCG has been used in clinical practice for the last two decades and its efficacy against stress-induced thoracic pain has been suggested. Although SOCG has been used as an herbal formula in Korean medicine, its toxicity has not yet been evaluated. In this study, we evaluated the safety of SOCG through a 13-week general toxicity study in rats.

MATERIAL AND METHODS

SOCG was administered by oral gavage to rats at doses of 0 (control), 800, 2000, and 5000mg/kg/day over a 13-week period. Toxicity testing was conducted by evaluating mortality, clinical signs, body weight, food consumption, urinalysis, hematology, serum biochemistry, organ weight, necropsy, and histopathology compared with the concurrent control.

RESULTS

SOCG-related changes were noted in clinical signs and urinalysis. The observed clinical signs were compound-colored stool and salivation. Urinalysis results revealed brown or amber colored urine and elevated levels of protein. However, these changes were not considered to be adverse.

CONCLUSIONS

The no-observed-adverse-effect-level of SOCG was determined to be above 5000mg/kg in both male and female rats. The result of this study can lay the foundation for the application of SOCG in humans and prove useful for detailed investigations on the toxicity or pharmacological effects of SOCG.

Antinociceptive Profile of Levo-tetrahydropalmatine in Acute and Chronic Pain Mice Models: Role of spinal sigma-1 receptor

We have recently reported that repeated systemic treatments of extract from Corydalis yanhusuo alleviate neuropathic pain and levo-tetrahydropalmatine (l-THP) is one of active components from Corydalis. We designed this study to investigate antinociceptive effect of l-THP in acute and chronic pain models and related mechanism within the spinal cord. We found that intraperitoneal pretreatment with l-THP significantly inhibited the second phase of formalin-induced pain behavior. In addition, intrathecal as well as intraperitoneal pretreatment with l-THP reduced the mechanical allodynia (MA) induced by direct activation of sigma-1 receptor (Sig-1). In chronic constriction injury mice, these treatments remarkably suppressed the increase in MA and spinal phosphorylation of the NMDA receptor NR1 subunit expression on day 7 after surgery. Intrathecal treatment with l-THP combined with the Sig-1R antagonist, BD1047 synergistically blocked MA suggesting that l-THP modulates spinal Sig-1R activation. CatWalk gait analysis also supported that antinociceptive effect of l-THP as demonstrated by restoration of percentages of print area and single stance. Meanwhile, intrathecal pretreatment with naloxone, non-selective opioid receptor antagonist, did not affect the effect of l-THP. In conclusion, these results demonstrate that l-THP possesses antinociceptive effects through spinal Sig-1R mechanism and may be a useful analgesic in the management of neuropathic pain.

Safety and efficacy of Tongkuaixiao ointment in reliving cancer-induced pain: a multicenter double-blind placebo-controlled randomized trial

OBJECTIVE

To evaluate the safety and efficacy of Tongkuaixiao ointment (TKXO) in treating moderate-to-severe cancer induced somatalgia.

METHODS

Totally 130 patients with moderateto-severe cancer induced somatalgia were randomly divided into a TKXO group and a control group. The patients were treated with either TKXO applied externally or placebo, with opioid analgesics orally at the same time. Observation parameters were included numerical rating scale (NRS) scores, analgesic efficacy, initiation effective time, persistent analgesic time, equivalent morphine dose, National Comprehensive Cancer Network (NCCN) grade in Impact of Pain Measurement Scores, and safety and satisfaction extent investigation.

RESULTS

NRS scores and NCCN grade in Impact of Pain Measurement Scores decreased significantly after 5-days' treatment in the two groups (P < 0.0001). Compared to the control group, initiation effective time was significantly shorter (P < 0.05) and persistent analgesic time was significantly longer (P < 0.01), equivalent oral morphine doses of the first day and the whole treatment course were significantly decreased in the TKXO treatment group (P < 0.01 or P < 0.05). No obvious adverse effects were found in the TKXO group.

CONCLUSION

TKXO combined with opioid analgesics possesses the advantages of high efficacy, fast action, long persistent action, safety and convenience in use, and it can reduce the dose of opioid.

The Antinociceptive Properties of the Corydalis yanhusuo Extract

Corydalis yanhusuo. W.T. extracts (YHS) are widely used for the treatment of pain and inflammation. There are a few studies that assessed the effects of YHS in pain assays; however, none of these studies has systematically compared its activities in the different pain animal modes namely: acute, inflammatory and chronic pain. Furthermore, little is known about the mechanism of YHS activity in these assays. The aim of this study was to systematically evaluate the antinociceptive properties of YHS by testing it in four standardized pain assays and to investigate its mechanism. YHS antinociceptive properties were analyzed in the tail flick, the formalin paw licking, the von Frey filament and the hot box assays after spinal nerve ligation, which monitors acute nociceptive, persistent inflammatory and chronic neuropathic pain, respectively. YHS pharmacological profile was determined by screening it against a battery of G-protein coupled receptors and its mechanism of action was studied using knock-out mice. Our study shows that YHS, at a non-sedative dose, increases the tail flick latency in the tail flick assay without resulting in development of tolerance. YHS also decreases paw licking time in the formalin assay. Further, YHS increases paw withdraw threshold and latency in the von Frey filament and the hot box assays, respectively. In vitro, YHS exhibits prominent dopamine receptor antagonistic properties. In dopamine D2 receptor knockout mice, its antinociceptive effects are attenuated in acute and neuropathic pain but not inflammatory pain assays. Our results therefore indicate that YHS effectively attenuates acute, inflammatory and neuropathic pain, without causing tolerance. The effects on acute and neuropathic pain, but not inflammatory pain, are at least partially mediated through dopamine D2 receptor antagonism. Since YHS is a dietary supplement commercially available in the United States, our data suggest that it might be a candidate for alternative pain treatment.

A Traditional Chinese Medicine Xiao-Ai-Tong Suppresses Pain through Modulation of Cytokines and Prevents Adverse Reactions of Morphine Treatment in Bone Cancer Pain Patients

Treating cancer pain continues to possess a major challenge. Here, we report that a traditional Chinese medicine Xiao-Ai-Tong (XAT) can effectively suppress pain and adverse reactions following morphine treatment in patients with bone cancer pain. Visual Analogue Scale (VAS) and Quality of Life Questionnaire (EORTC QLQ-C30) were used for patient's self-evaluation of pain intensity and evaluating changes of adverse reactions including constipation, nausea, fatigue, and anorexia, respectively, before and after treatment prescriptions. The clinical trials showed that repetitive oral administration of XAT (200 mL, bid, for 7 consecutive days) alone greatly reduced cancer pain. Repetitive treatment with a combination of XAT and morphine (20 mg and 30 mg, resp.) produced significant synergistic analgesic effects. Meanwhile, XAT greatly reduced the adverse reactions associated with cancer and/or morphine treatment. In addition, XAT treatment significantly reduced the proinflammatory cytokines interleukin-1β and tumor necrosis factor-α and increased the endogenous anti-inflammatory cytokine interleukin-10 in blood. These findings demonstrate that XAT can effectively reduce bone cancer pain probably mediated by the cytokine mechanisms, facilitate analgesic effect of morphine, and prevent or reduce the associated adverse reactions, supporting a use of XAT, alone or with morphine, in treating bone cancer pain in clinic.

Studies on the analgesic activities of Jia-Yuan-Qing pill and its safety evaluation in mice

The analgesic activity of Porcellio laevis Latreille, Rhizoma Corydalis, and Radix Cynanchi Paniculati have been reported in recent years. A new formula named Jia-Yuan-Qing pill (JYQP) is therefore created by combining the three herbs at 9:7:7 ratio according to traditional Chinese theories. The present study aims to evaluate the effect of JYQP as a novel painkiller in various models. Acute toxicity test was applied to evaluate the safety of JYQP. Acetic-acid-induced writhing, hot plate test, formalin test, and naloxone-pretreated writhing test were employed to elaborate the analgesic activity of JYQP and its possible mechanism. A bone cancer pain mouse model was performed to further assess the effect of JYQP in relieving cancer pain. Test on naloxone-precipitated withdrawal symptoms was conduct to examine the physical dependence of mice on JYQP. Data revealed that JYQP reduced writhing and stretching induced by acetic acid; however, this effect could not be blocked by naloxone. JYQP specifically suppressed the phase II reaction time in formalin-treated mice; meanwhile, no analgesic effect of JYQP in hot plate test was observed, indicating that JYQP exerts analgesic activity against inflammatory pain rather than neurogenic pain. Furthermore, JYQP could successfully relieve bone cancer pain in mice. No physical dependence could be observed upon long-term administration in mice. Collectively, our present results provide experimental evidence in supporting clinical use of JYQP as an effective and safe agent for pain treatment.

First evidence of the analgesic activity of govaniadine, an alkaloid isolated from Corydalis govaniana Wall

In this work, govaniadine, an alkaloid isolated from Corydalis govaniana Wall. was evaluated for its analgesic activity by writhing and hot-plate tests. Govaniadine did not display any toxic effects in mice up to 20 mg/kg during 24 h assessment study. The acetic acid-induced writhing was significantly reduced by pretreatment with govaniadine in a dose-dependent manner (1.25-5.0 mg/kg, intraperitoneally (i.p.)). Furthermore, molecular docking study has shown that this alkaloid binds the COX-2 enzyme. In the hot-plate test, govaniadine at dose of 2.5 and 5 mg/kg, i.p. displayed analgesic effect at all time points (30, 60, 90 and 120 min). The analgesic effect of govaniadine was significantly antagonised by naloxone administration. Our results demonstrate for the first time that the peripheral and central analgesic effects of govaniadine could be in part related to the involvement of COX-2 activity and by its interaction with the opioid system.

Up-regulation on cytochromes P450 in rat mediated by total alkaloid extract from Corydalis yanhusuo

Background

Yanhusuo (Corydalis yanhusuo W.T. Wang; YHS), is a well-known traditional Chinese herbal medicine, has been used in China for treating pain including chest pain, epigastric pain, and dysmenorrhea. Its alkaloid ingredients including tetrahydropalmatine are reported to inhibit cytochromes P450 (CYPs) activity in vitro. The present study is aimed to assess the potential of total alkaloid extract (TAE) from YHS to effect the activity and mRNA levels of five cytochromes P450 (CYPs) in rat.

Methods

Rats were administered TAE from YHS (0, 6, 30, and 150 mg/kg, daily) for 14 days, alanine aminotransferase (ALT) levels in serum were assayed, and hematoxylin and eosin-stained sections of the liver were prepared for light microscopy. The effects of TAE on five CYPs activity and mRNA levels were quantitated by cocktail probe drugs using a rapid chromatography/tandem mass spectrometry (LC-MS/MS) method and reverse transcription-polymerase chain reaction (RT-PCR), respectively.

Results

In general, serum ALT levels showed no significant changes, and the histopathology appeared largely normal compared with that in the control rats. At 30 and 150 mg/kg TAE dosages, an increase in liver CYP2E1 and CYP3A1 enzyme activity were observed. Moreover, the mRNA levels of CYP2E1 and CYP3A1 in the rat liver, lung, and intestine were significantly up-regulated with TAE from 6 and 30 mg/kg, respectively. Furthermore, treatment with TAE (150 mg/kg) enhanced the activities and the mRNA levels of CYP1A2 and CYP2C11 in rats. However, the activity or mRNA level of CYP2D1 remained unchanged.

Conclusions

These results suggest that TAE-induced CYPs activity in the rat liver results from the elevated mRNA levels of CYPs. Co-administration of prescriptions containing YHS should consider a potential herb (drug)–drug interaction mediated by the induction of CYP2E1 and CYP3A1 enzymes.

Ginsenosides Have a Suppressive Effect on c-Fos Expression in Brain and Reduce Cardiovascular Responses Increased by Noxious Stimulation to the Rat Tooth

The purpose of this study is to investigate the antinociceptive effects of ginsenosides on toothache. c-Fos immunoreactive (IR) neurons were examined after noxious intrapulpal stimulation (NS) by intrapulpal injection of 2 M KCl into upper and lower incisor pulps exposed by bone cutter in Sprague Dawley rats. The number of Fos-IR neurons was increased in the trigeminal subnucleus caudalis (Vc) and the transitional region between Vc and subnucleus interpolaris (Vi) by NS to tooth. The intradental NS raised arterial blood pressure (BP) and heart rate (HR). The number of Fos-IR neurons was also enhanced in thalamic ventral posteromedial nucleus (VPMN) and centrolateral nucleus (CLN) by NS to tooth. The intradental NS increased the number of Fos-IR neurons in the nucleus tractus solitarius (NTS) and rostral ventrolateral medulla (RVLM), hypothalamic supraoptic nucleus (SON) and paraventricular nucleus (PVN), central cardiovascular regulation centers. Ginsenosides reduced the number of c-Fos-IR increased by NS to tooth in the trigeminal Vc and thalamic VPMN and CLN. Naloxone, an opioid antagonist, did not block the effect of ginsenoside on the number of Fos-IR neurons enhanced by NS to tooth in the trigeminal Vc and thalamic VPMN and CLN. Ginsenosides ameliorated arterial BP and HR raised by NS to tooth and reduced the number of Fos-IR neurons increased by NS to tooth in the NTS, RVLM, hypothalamic SON, and PVN. These results suggest that ginsenosides have an antinociceptive effect on toothache through non-opioid system and attenuates BP and HR increased by NS to tooth.