Endomorphin-2 analogs with C-terminal esterification display potent antinociceptive effects in the formalin pain test in mice.

Previously, we have investigated three C-terminal esterified endomorphin-2 (EM-2) analogs EM-2-Me, EM-2-Et and EM-2-Bu with methyl, ethyl and tert-butyl ester modifications, respectively. These analogs produced significant antinociception in acute pain at the spinal and supraspinal levels, with reduced tolerance and gastrointestinal side effects. The present study was undertaken to determine the analgesic effects and opioid mechanisms of these three analogs in the formalin pain test. Our results demonstrated that intracerebroventricular (i.c.v.) administration of 0.67-20 nmol EM-2 analogs EM-2-Me, EM-2-Et and EM-2-Bu produced dose-dependent antinociceptive effects in both phase Ⅰ and phase Ⅱ of formalin pain. EM-2-Me and EM-2-Bu displayed more potent antinociception than morphine. Especially, EM-2-Bu exhibited the highest antinociception in phase Ⅱ of formalin pain, with the ED50 value being 2.1 nmol. Naloxone (80 nmol, i.c.v.) completely antagonized the antinociceptive effects of EM-2-Me, EM-2-Et and EM-2-Bu (20 nmol, i.c.v.) in both phase I and phase Ⅱ of formalin pain, suggesting a central opioid mechanism. Nevertheless, the antinociception induced by EM-2-Me might be involved in the release of dynorphin A, which subsequently acted on κ- opioid receptor. EM-2-Bu produced the antinociception probably by the direct activation of both µ- and δ-opioid receptors. EM-2-Me, EM-2-Et and EM-2-Bu also produced significant analgesic effects after peripheral administration, and the central opioid receptors were involved. Furthermore, EM-2-Bu had no influence on the locomotor activity after i.c.v. injection. The present investigation demonstrated that C-terminal esterified modifications of EM-2 will be beneficial for developing novel therapeutics in formalin pain.

Novel endomorphin analogues CEMR-1 and CEMR-2 produce potent and long-lasting antinociception with a favourable side effect profile at the spinal level.

BACKGROUND AND PURPOSE: Endomorphins have shown great promise as pharmaceutics for the treatment of pain. We have previously confirmed that novel endomorphin analogues CEMR-1 and CEMR-2 behaved as potent µ agonists and displayed potent antinociceptive activities at the supraspinal and peripheral levels. The present study was undertaken to evaluate the antinociceptive properties of CEMR-1 and CEMR-2 following intrathecal (i.t.) administration. Furthermore, their antinociceptive tolerance and opioid-like side effects were also determined. EXPERIMENTAL APPROACH: The spinal antinociceptive effects of CEMR-1 and CEMR-2 were determined in a series of pain models, including acute radiant heat paw withdrawal test, spared nerve injury-induced neuropathic pain, complete Freund's adjuvant-induced inflammatory pain, visceral pain and formalin pain. Antinociceptive tolerance was evaluated in radiant heat paw withdrawal test. KEY RESULTS: Spinal administration of CEMR-1 and CEMR-2 produced potent and prolonged antinociceptive effects in acute pain. CEMR-1 and CEMR-2 may produce their antinociception through distinct µ receptor subtypes. These two analogues also exhibited significant analgesic activities in neuropathic, inflammatory, visceral and formalin pain at the spinal level. It is noteworthy that CEMR-1 showed non-tolerance-forming analgesic properties, while CEMR-2 exhibited substantially reduced antinociceptive tolerance. Furthermore, both analogues displayed no or reduced side effects on conditioned place preference response, physical dependence, locomotor activity and gastrointestinal transit. CONCLUSIONS AND IMPLICATIONS: The present investigation demonstrated that CEMR-1 and CEMR-2 displayed potent and long-lasting antinociception with a favourable side effect profile at the spinal level. Therefore, CEMR-1 and CEMR-2 might serve as promising analgesic compounds with minimal opioid-like side effects.

Human neural stem cells.

'Human neural stem cells' jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research, is the first guideline for human neural stem cells (hNSCs) in China. This standard specifies the technical requirements, test methods, test regulations, instructions for use, labelling requirements, packaging requirements, storage requirements, transportation requirements and waste disposal requirements for hNSCs, which is applicable to the quality control for hNSCs. It was originally released by the China Society for Cell Biology on 30 August 2022. We hope that publication of the guideline will facilitate institutional establishment, acceptance and execution of proper protocols, and accelerate the international standardization of hNSCs for clinical development and therapeutic applications.

Human midbrain dopaminergic progenitors.

Human midbrain dopaminergic progenitors (mDAPs) are one of the most representative cell types in both basic research and clinical applications. However, there are still many challenges for the preparation and quality control of mDAPs, such as the lack of standards. Therefore, the establishment of critical quality attributes and technical specifications for mDAPs is largely needed. "Human midbrain dopaminergic progenitor" jointly drafted and agreed upon by experts from the Chinese Society for Stem Cell Research, is the first guideline for human mDAPs in China. This standard specifies the technical requirements, test methods, inspection rules, instructions for usage, labelling requirements, packaging requirements, storage requirements, transportation requirements and waste disposal requirements for human mDAPs, which is applicable to the quality control for human mDAPs. It was originally released by the China Society for Cell Biology on 30 August 2022. We hope that the publication of this guideline will facilitate the institutional establishment, acceptance and execution of proper protocols, and accelerate the international standardization of human mDAPs for clinical development and therapeutic applications.

Endostatin 33 Peptide Is a Deintegrin α6ß1 Agent That Exerts Antitumor Activity by Inhibiting the PI3K-Akt Signaling Pathway in Prostate Cancer.

BACKGROUND: Prostate cancer (PCa) is the leading cause of death in men and has poor therapeutic outcomes. METHODS: A novel endostatin 33 peptide was synthesized by adding a specific QRD sequence on the basis of the endostatin 30 peptide (PEP06) with antitumor activity. Then, bioinformatic analysis and subsequent experiments were performed to validate the antitumor function of this endostatin 33 peptide. RESULTS: We found that the 33 polypeptides significantly inhibited growth, invasion and metastasis and promoted the apoptosis of PCa in vivo or vitro, which is more significant than PEP06 under the same conditions. According to 489 cases from the TCGA data portal, the α6ß1 high expression group was closely associated with the poor prognosis (Gleason score, pathological N stage, etc.) of PCa and was mainly enriched in the PI3K-Akt pathway. Subsequently, we demonstrated that endostatin 33 peptide can down-regulate the PI3K-Akt pathway via the targeted inhibition of α6ß1, thereby inhibiting the epithelial-mesenchymal transition and matrix metalloproteinase in C42 cell lines. CONCLUSION: The endostatin 33 peptide can exert antitumor effects by inhibiting the PI3K-Akt pathway, especially in tumors with a high expression of the integrin α6ß1 subtype, such as prostate cancer. Therefore, our study will provide a new method and theoretical basis for the treatment of prostate cancer.

Mechanism Study on Chinese Medicine in Treatment of Nodular Goiter.

Nodular goiter has become increasingly prevalent in recent years. Clinically, there has been a burgeoning interest in nodular goiter due to the risk of progression to thyroid cancer. This review aims to provide a comprehensive summary of the mechanisms underlying the therapeutic effect of Chinese medicine (CM) in nodular goiter. Articles were systematically retrieved from databases, including PubMed, Web of Science and China National Knowledge Infrastructure. New evidence showed that CM exhibited multi-pathway and multi-target characteristics in the treatment of nodular goiter, involving hypothalamus-pituitary-thyroid axis, oxidative stress, blood rheology, cell proliferation, apoptosis, and autophagy, especially inhibition of cell proliferation and promotion of cell apoptosis, involving multiple signal pathways and a variety of cytokines. This review provides a scientific basis for the therapeutic use of CM against nodular goiter. Nonetheless, future studies are warranted to identify more regulatory genes and pathways to provide new approaches for the treatment of nodular goiter.

Tubeimoside-1: A review of its antitumor effects, pharmacokinetics, toxicity, and targeting preparations.

Tubeimoside-1 (TBMS-1), a natural triterpenoid saponin found in traditional Chinese herbal medicine Bolbostemmatis Rhizoma, is present in numerous Chinese medicine preparations. This review aims to comprehensively describe the pharmacology, pharmacokinetics, toxicity and targeting preparations of TBMS-1, as well the therapeutic potential for cancer treatement. Information concerning TBMS-1 was systematically collected from the authoritative internet database of PubMed, Web of Science, and China National Knowledge Infrastructure applying a combination of keywords involving "tumor," "pharmacokinetics," "toxicology," and targeting preparations. New evidence shows that TBMS-1 possesses a remarkable inhibitory effect on the tumors of the respiratory system, digestive system, nervous system, genital system as well as other systems in vivo and in vitro. Pharmacokinetic studies reveal that TBMS-1 is extensively distributed in various tissues and prone to degradation by the gastrointestinal tract after oral administration, causing a decrease in bioavailability. Meanwhile, several lines of evidence have shown that TBMS-1 may cause adverse and toxic effects at high doses. The development of liver-targeting and lung-targeting preparations can reduce the toxic effect of TBMS-1 and increase its efficacy. In summary, TBMS-1 can effectively control tumor treatment. However, additional research is necessary to investigate in vivo antitumor effects and the pharmacokinetics of TBMS-1. In addition, to reduce the toxicity of TBMS-1, future research should aim to modify its structure, formulate targeting preparations or combinations with other drugs.

An Ultrasound-Induced Self-Clearance Hydrogel for Male Reversible Contraception.

Nearly half of pregnancies worldwide are unintended mainly due to failure of contraception, resulting in negative effects on women's health. Male contraception techniques, primarily condoms and vasectomy, play a crucial role in birth control, but cannot be both highly effective and reversible at the same time. Herein, an ultrasound (US)-induced self-clearance hydrogel capable of real-time monitoring is utilized for in situ injection into the vas deferens, enabling effective contraception and noninvasive recanalization whenever needed. The hydrogel is composed of (i) sodium alginate (SA) conjugated with reactive oxygen species (ROS)-cleavable thioketal (SA-tK), (ii) titanium dioxide (TiO2), which can generate a specific level of ROS after US treatment, and (iii) calcium chloride (CaCl2), which triggers the formation of the hydrogel. For contraception, the above mixture agents are one-time injected into the vas deferens, which can transform from liquid to hydrogel within 160 s, thereby significantly physically blocking the vas deferens and inhibiting movability of sperm. When fertility is needed, a noninvasive remedial ultrasound can make TiO2 generate ROS, which cleaves SA-tK to destroy the network of the hydrogel. Owing to the recanalization, the refertility rate is restored to 100%. Meanwhile, diagnostic ultrasound (D-US, 22 MHz) can monitor the occlusion and recanalization process in real-time. In summary, the proposed hydrogel contraception can be a reliable, safe, and reversible male contraceptive strategy that addresses an unmet need for men to control their fertility.

Novel Cyclic Endomorphin Analogues with Multiple Modifications and Oligoarginine Vector Exhibit Potent Antinociception with Reduced Opioid-like Side Effects.

Endomorphins (EMs) are potent pharmaceuticals for the treatment of pain. Herein, we investigated several novel EM analogues with multiple modifications and oligoarginine conjugation. Our results showed that analogues 1-6 behaved as potent µ-opioid agonists and enhanced stability and lipophilicity. Analogues 5 and 6 administered centrally and peripherally induced significant and prolonged antinociceptive effects in acute pain. Both analogues also produced long-acting antiallodynic effects against neuropathic and inflammatory pain. Furthermore, they showed a reduced acute antinociceptive tolerance. Analogue 6 decreased the extent of chronic antinociceptive tolerance, and analogue 5 exhibited no tolerance at the supraspinal level. Particularly, they displayed nontolerance-forming antinociception at the peripheral level. In addition, analogues 5 and 6 exhibited reduced or no opioid-like side effects on gastrointestinal transit, conditioned place preference (CPP), and motor impairment. The present investigation established that multiple modifications and oligoarginine-vector conjugation of EMs would be helpful in developing novel analgesics with fewer side effects.

The spinal anti-allodynic effects of endomorphin analogs with C-terminal hydrazide modification in neuropathic pain model.

The present study was undertaken to further investigate the spinal anti-allodynic effects of endomorphins (EMs) and their C-terminal hydrazide modified analogs EM-1-NHNH2 and EM-2-NHNH2 in the spared nerve injury (SNI) model of neuropathic pain in mice. Our results demonstrated that intrathecal (i.t.) administration of endomorphin-1 (EM-1), endomorphin-2 (EM-2), EM-1-NHNH2 and EM-2-NHNH2 produced potent anti-allodynic effects ipsilaterally in neuropathic pain model. Judging from the area under the curve (AUC) values, these two analogs exhibited higher antinociception than their parent peptides. Moreover, they also displayed significant antinociceptive effects in the contralateral paw administered intrathecally. Interestingly, EM-1 and its analog EM-1-NHNH2 displayed their antinociception probably by µ2-opioid receptor subtype since the µ1-opioid receptor antagonist naloxonazine didn't significantly block the anti-allodynia of EM-1 and EM-1-NHNH2, which implied a same opioid mechanism. However, the anti-allodynia induced by EM-2, but not EM-2-NHNH2 was significantly reduced by both µ1-opioid antagonist, naloxonazine and κ-antagonist, nor-binaltorphamine (nor-BNI), indicating multiple opioid receptors were involved in the anti-allodynic effects of EM-2. Most importantly, EM-1-NHNH2 decreased the antinociceptive tolerance, and EM-2-NHNH2 displayed non-tolerance-forming antinociception. Therefore, C-terminal amide to hydrazide conversion changed the spinal antinociceptive profiles of EMs in neuropathic pain. The present investigation is of great value in the development of novel opioid therapeutics against neuropathic pain.

Organocatalytic Control over a Fuel-Driven Transient-Esterification Network*.

Signal transduction in living systems is the conversion of information into a chemical change, and is the principal process by which cells communicate. In nature, these functions are encoded in non-equilibrium (bio)chemical reaction networks (CRNs) controlled by enzymes. However, man-made catalytically controlled networks are rare. We incorporated catalysis into an artificial fuel-driven out-of-equilibrium CRN, where the forward (ester formation) and backward (ester hydrolysis) reactions are controlled by varying the ratio of two organocatalysts: pyridine and imidazole. This catalytic regulation enables full control over ester yield and lifetime. This fuel-driven strategy was expanded to a responsive polymer system, where transient polymer conformation and aggregation are controlled through fuel and catalyst levels. Altogether, we show that organocatalysis can be used to control a man-made fuel-driven system and induce a change in a macromolecular superstructure, as in natural non-equilibrium systems.

[Effects of light intensity on physio-biochemical characteristics of Chrysanthemum indicum].

By analyzing the effects of light intensity on the growth, physiological and biochemical characteristics of Chrysanthemum indicum, the light intensity suitable for the growth of Ch. indicum was revealed, which provided a reference for the planting of Ch. indicum. There were five treatment groups of Ch. indicum, which was planted under 100%, 80%, 60%, 40% and 20% all natural light intensity conditions, respectively. In the meantime, these indicators of photosynthetic physiology, such as relative growth, photosynthetic pigment content, photosynthetic parameters, and chlorophyll fluorescence parameters etc. were measured in the peak period of growth of Ch. indicum as well as related indicators of the protective enzyme system, and the ultrastructure of chloroplast was observed with the use of transmission electron microscope technique. In our study, the results showed that the leaves of Ch. indicum occurred yellow phenomenon in different degrees when Ch. indicum was placed at more than 80% of the total natural light intensity condition, the height and stem diameter of plant reached the maximum at 60% of the total natural light intensity. More importantly, the number of branches of Ch. indicum was significantly increased under the total natural light intensity of more than 60%. Both the content of photosynthetic pigment and net photosynthetic rate were negatively correlated with light intensity, while photosynthetic parameters and chlorophyll fluorescence parameters showed a trend of rising first and then decreasing with the decrease of light intensity. The physiological indexes of Ch.indicum including stomatal conductivity, intracellular CO_2 concentration, transpiration rate, water use efficiency and actual photochemical quantum yield of PS Ⅱ had been determined, and the results showed that all of them were at the highest level under 60% total natural light intensity condition. The chloroplast structure of Ch. indicum was not obviously abnormal under 60% and 80% total natural light intensity treatments, but the stroma lamella was broken under 100% total natural light intensity, and not only the number of chloroplast, but also the number and volume of starch grains were decreased significantly under 20% and 40% total natural light intensity. With the decrease of light intensity, the enzymes activities of SOD and CAT decreased, the activity of POD increased in the early stage and decreased in the later stage, and the content of MDA showed a decreasing trend. The analysis of results indicated that the Ch. indicum can grow under 20%-100% total natural light intensity, but the best growth condition was under 60% total natural light intensity.

[Treatment of intertrochanteric fracture of femur with closed reduction of proximal femoral anti rotation intramedullary nail in supine position].

OBJECTIVE: To investigate the effect and feasibility of closed reduction and internal fixation with PFNA in the treatment of intertrochanteric fracture of femur in the supine position without traction bed. METHODS: From June 2014 to March 2018, 45 patients with intertrochanteric fracture of femur who were treated and followed up were analyzed retrospectively. There were 21 males and 24 females, with an average age of 67.4 years (43 to 92 years);18 cases on the left side and 27 on the right side. According to Evans Jensen classification, there were 7 patients of type Ⅱ, 17 patients of type Ⅲ, 16 patients of type Ⅳ and 5 patients of type Ⅴ. The time from injury to operationwas 2 to 6 days. The operation time, blood loss and fracture healing, closing time, postoperative complications and Harris score of hip joint were recorded. RESULTS: The operation time of 45 patients was 35 to 80 min, with an average of 52.6 min;the intraoperative bleeding volume was 40 to 110 ml, with an average of 68.7 ml;the hospitalization time was 6 to 11 days, with an average of 8.4 days;the follow up time was 12 to 18 months, with an average of 14.7 months;the internal fixation of 2 patients failed, and 43 patients achieved bony healing;the deep vein thrombosis of the lower extremity in the perioperative period was 1 case, and the inferior vena cava filter was inserted;the internal fixation of 2 patients was cut out, and the hip was renovated. The incidence of complications was 8.9%(4 / 45). At the final follow up, Harris score of hip joint was 56 to 95 (81.30±8.40), including excellent 15 cases, good 26 cases, fair 2 cases and poor 2 cases. CONCLUSION: It is safe and feasible to treat intertrochanteric fracture of femur with closed reduction and anti rotation intramedullary nailing under the bed without traction in a supine position. It has the advantages of small trauma and low complications, and the clinical effect is satisfactory. It is worth popularizing and using in basic hospitals.

[Effect of nitrogen,phosphorus and potassium formula fertilizer on growth and chemical composition content of Inula japonica].

Inula japonica was used as the research object, "3414" fertilization experiment were conducted to study the effects of nitrogen,phosphorus and potassium formula fertilizer on the growth and chemical composition content of I. japonica. The characteristics of fertilizer requirement were preliminarily revealed and the study provided fertilization guidance for artificial cultivation of I. japonica. The results showed that different nitrogen,phosphorus and potassium formula fertilizers had significant effects on plant morphology,physiological and biochemical indexes,dry matter accumulation and chemical composition content. The growth indexes and chemical components of I. japonica showed an upward trend with the increase of fertilization amount,especially the nitrogen fertilizer was the most significant. The indicators were analyzed by membership function. After comprehensive evaluation,the optimal nitrogen,phosphorus and potassium formula fertilization level was N3 P2 K2,namely high level nitrogen fertilizer,medium level phosphorus fertilizer and potassium fertilizer. I. japonica is a high fertilizer demand plant,and the rational fertilization scheme is " applying nitrogen fertilizer again and applying phosphorus and potassium fertilizer properly".

Endomorphin-1 analogs with oligoarginine-conjugation at C-terminus produce potent antinociception with reduced opioid tolerance in paw withdrawal test.

For clinical use, it is essential to develop potent endomorphin (EM) analogs with reduced antinociceptive tolerance. In the present study, the antinociceptive activities and tolerance development of four potent EM-1 analogs with C-terminal oligoarginine-conjugation was evaluated and compared in the radiant heat paw withdrawal test. Following intracerebroventricular (i.c.v.) administration, all analogs 1-4 produced potent and prolonged antinociceptive effects. Notably, analogs 2 and 4 with the introduction of D-Ala in position 2 exhibited relatively higher analgesic potencies than those of analogs 1 and 3 with ß-Pro substitution, consistent with their µ-opioid binding characteristic. In addition, at a dose of 50 µmol/kg, endomorphin-1 (EM-1) failed to produce any significant antinociceptive activity after peripheral administration, whereas analogs 1-4 induced potent antinociceptive effects with an increased duration of action. Herein, our results indicated the development of antinociceptive tolerance to EM-1 and morphine at the supraspinal level on day 7. By contrast, analogs 1-4 decreased the antinociceptive tolerance. Furthermore, subcutaneous (s.c.) administration of morphine at 50 µmol/kg also developed the antinociceptive tolerance, whereas the extent of tolerance developed to analogs 1-4 was largely reduced. Especially, analog 4 exhibited non-tolerance-forming antinociception after peripheral administration. The present investigation gave the evidence that C-terminal conjugation of EM-1 with oligoarginine vector will facilitate the development of novel opioid analgesics with reduced opioid tolerance.

[Effects of compound planting on growth and quality of Salvia miltiorrhiza].

The effects of four kinds of different plant populations on the morphology, the dry matter accumulation, active ingredient content and antioxidant activty in vitro of Salvia miltiorrhiza were analyzed by setting up four kinds of mixed planting groups, such as S. miltiorrhiza and Cassia obtusifolia, Capsicum annuum, Perilla frutescens and Zea mays. And through the root isolation treatment, we preliminarily explored the formation mechanism of the four kinds of matching plants of the yield and quality of S. miltiorrhiza, and chose the matching plants suitable for the establishment of the compound population with S. miltiorrhiza,and provided the basis for constructing high efficiency compound planting pattern of S. miltiorrhiza. The results showed that there were significant differences in plant morphology, dry matter accumulation of root, active ingredient content and antioxidant activty in vitro of S. miltiorrhiza in different compound population mixed. The growth and yield of S. miltiorrhiza were unfavorable to the combination planting of Cassia obtusifolia, Z. mays and Salvia miltiorrhiza.The compound planting of P. frutescens and S. miltiorrhiza significantly promoted the growth of S. miltiorrhiza, but significantly reduced the quality of S. miltiorrhiza.The yield and quality of S. miltiorrhiza were significantly improved by the combination of C. annuum and S. miltiorrhiza. Therefore, among the four plants of C. obtusifolia, C. annuum, P. frutescens, and Z. mays, the P. frutescens of Solanaceae is the best matching species for the construction of compound planting group with S. miltiorrhiza.

[Effect of compound planting on soil physical and chemical properties and soil enzyme activities of Salvia miltiorrhiza].

The effects of four kinds of different plant populations on the soil physical and chemical properties and soil enzyme activities of Salvia miltiorrhiza were analyzed by setting up four kinds of mixed planting groups, such as S. miltiorrhiza and Cassia obtusifolia, Capsicum annuum, Perilla frutescens and Zea mays. And through the root isolation treatment, we preliminarily explored the formation mechanism of the four kinds of matching plants of soil physical and chemical properties and soil enzyme activities of S. miltiorrhiza, and chose the matching plants suitable for the establishment of the compound population with S. miltiorrhiza,and provided the basis for constructing high efficiency compound planting pattern of S. miltiorrhiza. The results showed that there were significant differences in soil physical and chemical properties and soil enzyme activitiesof Salvia miltiorrhiza in different compound population mixed.The combination of C. obtusifolia, P. frutescens, Z. mays and S. miltiorrhiza mixed planting were all reduced the soil cation exchange capacity and soil enzyme activities, and increased the soil electric conductivity. The compound planting of P. frutescens and S. miltiorrhiza increased the soil cation exchange capacity and soil enzyme activities, and reduced the soil electric conductivity. Therefore,The compound planting population of P. frutescens and S. miltiorrhiza is conducive to improve soil physical and chemical properties and increase soil microbial activity, which is the best collocation species of S. miltiorrhiza.

[Analysis on character of mineral elements in Changium smyrnioides and rhizosphere soil].

The contents of 22 kinds of mineral elements in different parts of Changium smyrnioides and in the rhizosphere soil of 10 different populations were determined by microwave digestion-inductively coupled plasma atomic emission spectrometry (ICP-AES). The characteristics of mineral elements in the plants and the soil of main distribution area of Ch. smyrnioides was analyzed and the mechanism of the quality formation of Ch. smyrnioides was explored to provide the basis for the quality evaluation and cultivation regulation of Ch. smyrnioides.The results showed that the quality of soil environment was better in the main distribution area of Ch. smyrnioides, the content of trace elements was higher, the contents of P and K were lower and the contents of mineral elements in the soil of each distribution area was significantly different. The three elements of Se, P and K are significantly accumulated in the root of Ch. smyrnioides. There were significant differences in the total contents of mineral elements in the roots of Ch. smyrnioides in different producing areas. The contents of mineral elements in different parts of Ch. smyrnioides were significantly different. Ch.smyrnioides of the main distribution area of Ch. smyrnioides belonged to the safety level, the distribution of mineral elements in the plants can be used as an indicator of the quality of medicinal herbs.

C-terminal hydrazide modification changes the spinal antinociceptive profiles of endomorphins in mice.

Previously, we have demonstrated that endomorphins (EMs) analogs with C-terminal hydrazide modification retained the µ-opioid receptor affinity and selectivity, and exhibited potent antinociception after intracerebroventricular (i.c.v.) administration. In the present study, we extended our studies to evaluate the antinociceptive profiles of EMs and their analogs EM-1-NHNH2, EM-2-NHNH2 given spinally in the radiant heat paw withdrawal test. Following intrathecal (i.t.) administration, EM-1, EM-2, EM-1-NHNH2 and EM-2-NHNH2 dose-dependently increased the latency for paw withdrawal response. EM-1-NHNH2 displayed the highest antinociceptive effects, with the ED50 values being 1.63 nmol, more potent than the parent EM-1 (1.96 nmol), but with no significant difference. By contrast, the analgesic activities of EM-2 and its analog EM-2-NHNH2 were almost equivalent (P>0.05). Naloxone and ß-funaltrexamine (ß-FNA) almost completely attenuated the antinociceptive effects of EMs and their analogs EM-1-NHNH2, EM-2-NHNH2 (10 nmol, i.t.), indicating the involvement of µ-opioid receptors. Notably, the antinociception of EM-1 was not significantly antagonized by naloxonazine, a selective µ1-opioid receptor antagonist, but partially reversed the effects of EM-2, suggesting that EM-1 and EM-2 may produce antinociception through distinct µ1- and µ2-opioid receptor subtypes. Moreover, naloxonazine didn't significantly block the antinociceptive effects of EM-1-NHNH2 and EM-2-NHNH2, and nor-BNI, the κ-opioid receptor antagonist, attenuated the analgesic effects of EM-2, but not EM-1, EM-1-NHNH2 or EM-2-NHNH2. These results indicated that C-terminal amide to hydrazide conversion changed the antinociceptive opioid mechanisms of EM-2 but not EM-1 at the spinal level. Herein, the acute antinociceptive tolerance were further determined and compared. EM-1-NHNH2 and EM-2-NHNH2 shifted the dose-response curve rightward by only 2.8 and 1.5-fold as determined by tolerance ratio, whereas EM-1 and EM-2 by 3.4 and 4.6-fold, respectively, indicating substantially reduced antinociceptive tolerance. The present study demonstrated that C-terminal hydrazide modification changes the spinal antinociceptive profiles of EMs.

Antiallodynic Effects of Endomorphin-1 and Endomorphin-2 in the Spared Nerve Injury Model of Neuropathic Pain in Mice.

BACKGROUND: The spared nerve injury (SNI) model is a new animal model that can mimic several characteristics of clinical neuropathic pain. Opioids are recommended as treatment of neuropathic pain. Therefore, the present study was conducted to investigate the antinociceptive effects of endomorphin-1 (EM-1) and endomorphin-2 (EM-2) given centrally and peripherally in the SNI model of neuropathic pain in mice. METHODS: The SNI model was made in mice by sparing the sural nerve intact, when the other 2 of 3 terminal branches of the sciatic nerve (common peroneal and tibial nerves) were tightly ligated and cut. Von Frey monofilaments were used to measure the SNI-induced mechanical allodynia-like behavior. The antiallodynic effects of EM-1 and EM-2 were determined after central and peripheral administration in the SNI model of neuropathic pain. Also, the specific opioid receptor antagonists were used to determine the opioid mechanisms of EMs involved in neuropathic pain. Values were expressed as the mean ± standard deviation. RESULTS: Our results showed that the SNI mice developed prolonged mechanical allodynia-like behavior in ipsilateral paw after surgery, with the withdrawal threshold value being 0.061 ± 0.02 g after 14 days. EM-1 and EM-2 produced significant antiallodynic effects in ipsilateral paw after intracerebroventricular (i.c.v.) administration, more effective than that of morphine. The peak withdrawal thresholds of 10 nmol EM-1 and EM-2 determined at 5 minutes after injection were 0.92 ± 0.36 and 0.87 ± 0.33 g, respectively, higher than that of morphine (0.46 ± 0.20 g). Moreover, both EMs (10 nmol, i.c.v.) exerted significant antiallodynic effects in the contralateral paw, whereas no significant antinociceptive activity was seen after i.c.v. administration of morphine with equimolar dose. It was noteworthy that EM-1 and EM-2 produced antinociception through distinct µ1- and µ2-opioid receptor subtypes, and the EM-2-induced antiallodynia contained an additional component that was mediated by the release of endogenous dynorphin A, acting on κ-opioid receptor. In addition, the antiallodynic activities of peripheral administration of EM-1, EM-2, and morphine were also investigated. Intraplantar, but not subcutaneous administration of EM-1 and EM-2 also exhibited potent antinociception, establishing the peripheral and local effects. Both µ1- and µ2-opioid receptor subtypes, but not the δ- or κ-opioid receptors were involved in the peripheral antiallodynia of EMs. CONCLUSIONS: The present investigation demonstrated that both EM-1 and EM-2 given centrally and peripherally produced potent antiallodynic activities in SNI mice, and differential opioid mechanisms were involved.