Effects of gosha-jinki-gan, a kampo medicine, on peripheral tissue blood flow in streptozotocin-induced diabetic rats

Concurrent use of Chinese herbal medicine and anticoagulants may reduce major bleeding events

Background

This retrospective cohort study investigated the risk of major bleeding events during the concurrent use of Chinese herbal medicine (CHM) and anticoagulants in clinical practice.

Methods

A total of 4,470 patients receiving anticoagulant drugs were selected from Taiwan’s National Health Insurance Research Database (NHIRD). Half (n = 2,235) were also using CHMs (CHM cohort); the other half were not (non-CHM cohort). Each cohort was matched 1:1 using the propensity score. Chi-square testing and the Student’s t-test were used to examine differences between two cohorts. Cox proportional hazard regression analysis assessed the risks for major bleeding events in each cohort, as well as bleeding risks associated with specific CHM formulas and herbs. Cumulative incidence curves for major bleeding events were calculated using Kaplan-Meier analysis.

Results

Compared with the non-CHM cohort, the CHM cohort had a lower risk of overall bleeding events (p < 0.001) including hemorrhagic stroke (p = 0.008), gastrointestinal (GI) bleeding (p < 0.001), urogenital bleeding (p ≤ 0.001) and nasal/ear/eye bleeding (p = 0.004). Single herbs, such as Glycyrrhiza uralensis et Rhizoma, Panax notoginseng, Panax ginseng, Platycodon grandiflorum, Eucommia ulmoides Oliver and formulas, such as Shu Jing Huo Xue Tang, Shao Yao Gan Cao Tang and Ji Sheng Shen Qi Wan were associated with a lower risk of major bleeding events.

Conclusion

Using CHMs with anticoagulants appeared to decrease the risk of major bleeding, especially CHMs products containing Glycyrrhiza uralensis et Rhizoma, Panax notoginseng, Panax ginseng, Platycodon grandiflorum and Eucommia ulmoides Oliver. Further investigations are needed to determine whether CHM can maintain the therapeutic efficacy of anticoagulants while simultaneously reducing potential side effects.

Live-Imaging Analysis of Target Vessels and Nitric Oxide Production Associated with Gosha-Jinki-Gan and Keishi-Bukuryo-Gan: Two Herbal Preparations with Clinically Proven Blood Flow-Improving Effects but with Different Traditional Clinical Indicative Patterns

Gosha-jinki-gan (GJG) and Keishi-bukuryo-gan (KBG) are Kampo traditional herbal prescriptions used for different clinical patterns (sho) that improve blood flow. The pharmacological basis of the therapeutic choice remains unclear, although the clinical reliance of this pattern-based therapy is widely proven. We aimed to investigate their effects on microcirculation and nitric oxide (NO) kinetics using a live-imaging system to provide evidence for this. Live-imaging was performed in murine subcutaneous vessels and rat mesentery. In the subcutaneous vessels, we analyzed the effects of both drugs on the vessel diameter, blood flow velocity, and volume in the arteries, arterioles, and capillaries. In the rat mesentery, we induced the “oketsu” blood stasis using a stack of thin vinylidene chloride films and examined the effect on NO production using a fluorescent diaminofluorescein-2 diacetate. Following dissolution in hot water, 300 mg/kg of both drugs were administered intragastrically via a transesophageal catheter. Live-imaging analysis of subcutaneous blood flow revealed the different effects of GJG and KBG on their target vessels and effect onset. GJG targeted the capillaries and progressively increased the blood flow velocity and rate at 30–120 min after administration. No vasodilation or increased blood flow in the arteries and arterioles occurred. In contrast, KBG increased the diameter of the arterioles and arteries at 30–90 min after administration, and increased blood flow velocity and rate in arteries and arterioles. In a model of oketsu blood stasis in the mesenteric arteries, KBG increased the NO production from the vascular endothelial cells with dilatation of the arteriolar diameter. GJG improved blood flow mainly in the capillaries. Endothelial NO production decreased after GJG administration. The empirical treatment choice between GJG and KBG is based on the difference in target vessels and NO action and provides a pharmacological basis for therapy based on traditional medicine.

Mechanical allodynia triggered by cold exposure in mice with the Scn11a p.R222S mutation: a novel model of drug therapy for neuropathic pain related to NaV1.9

Mutations within the SCN11A gene which encodes the voltage-gated sodium channel NaV1.9 mainly expressed in small fiber sensory neurons have been associated with neuropathic disorders; however, suitable medications have not been fully investigated. To develop drug therapies against NaV1.9-related neuropathic pain, we aimed to establish a novel model using mice carrying the Scn11a p.R222S mutation initially identified in patients with familial episodic limb pain that is characterized by paroxysmal pain induced by fatigue or bad weather conditions. We investigated the influence of cold exposure (4 °C, overnight) on the behavioral and biochemical phenotypes of Scn11a p.R222S mutant (R222S) and wild type C57BL/6N (WT) mice. We also tested the effects of acetaminophen (125, 250 mg/kg, perorally, p.o.) and traditional Japanese medicine, goshajinkigan (0.5 or 1.0 g/kg, p.o.), which are analgesic drugs prescribed to patients with neuropathic pain, in this model of cold-induced mechanical allodynia in R222S mice.Cold-exposed R222S mice exhibited enhanced mechanical allodynia and thermal hypersensitivity compared with WT mice. The decrease of the mechanical withdrawal threshold in R222S mice was reversible 24 h after housing at room temperature. There was no significant change in the levels of interleukin-1β, interleukin-6, tumor necrosis factor-α, or interferon-γ in the plasma or spinal cords of WT and R222S mice after cold exposure. Both acetaminophen (250 mg/kg) and goshajinkigan (1.0 g/kg) significantly attenuated mechanical allodynia in R222S mice. The model of cold-induced mechanical allodynia in mice with the Scn11a p.R222S mutation is novel and useful for evaluating analgesic drugs for intractable neuropathies related to NaV1.9.

Clinical research on the efficacy and safety of Bosinji for low back pain with radiculopathy caused by herniated intervertebral disc of the lumbar spine: A protocol for a multicenter, randomized, controlled equivalence trial

BACKGROUND

A lumbar herniated intervertebral disc (LHIVD) is a common problem that usually causes low back pain and radiating pain. The effectiveness of Bosinji, one of the herbal medicines used for low back pain and radiating pain in patient with LHIVD, has been reported in several studies; however, little clinical evidence is available owing to the methodological limitations in previous studies. Hence, the present study aims to establish the clinical evidence regarding the efficacy and safety of Bosinji in improving pain, function, and quality of life in LHIVD patients.

METHOD/DESIGN

This is a multicenter, open-label, randomized, controlled, and equivalence trial with 2 parallel arms. A total of 74 patients who have low back pain and radiating pain due to LHIVD will be recruited and randomly allocated to the experimental group and control group. The patients in the experimental group and control group will take 2.5 g of Bosinji granule (1.523 g of Bosinji extract) or Loxonin tablet (60 mg of loxoprofen) 3 times a day for 6 weeks. Additionally, both groups will receive the same acupuncture treatment once a week for 6 weeks as a concurrent treatment. Changes in the 100-mm visual analogue scale (VAS) for low back pain after 6 weeks from baseline will be assessed as the primary outcome. Furthermore, the 100-mm VAS for radiating pain, Oswestry disability index (ODI), Roland-Morris disability questionnaire (RMDQ), EuroQol 5 Dimensions 5 Levels (EQ-5D-5L), global perceived effect (GPE), and deficiency syndrome of kidney index (DSKI) will be used to evaluate secondary outcomes. Outcomes will be assessed at baseline and at 3, 6, and 10 weeks after screening. For the safety evaluation, laboratory examinations including complete blood count, liver function test, renal function test, blood coagulation test, inflammation test, and urine analysis will be conducted before and after taking the medications.

DISCUSSION

The results of this trial will be used to establish clinical evidence regarding the use of Bosinji with acupuncture treatment in the treatment of patients with LHIVD.

TRIAL REGISTRATION NUMBER

NCT03386149 (clinicaltrials.gov) and KCT0002848 (Clinical Research Information Service of the Republic of Korea).

Efficacy of Japanese traditional (Kampo) medicine for treating chemotherapy-induced peripheral neuropathy: A retrospective case series study

AIM

To investigate Japanese traditional (Kampo) medicine’s effectiveness on cancer chemotherapy-induced peripheral neuropathy (CIPN), we carried out this retrospective study.

METHODS

By searching our outpatient database of 3154 patients who consulted our outpatient clinic of Japanese-Oriental (Kampo) Medicine at Chiba University Hospital from November 2005 to December 2010, a total of 281 patients diagnosed with cancer were identified. Twenty-four patients out of the 281 patients identified met the following three conditions and were eligible for further investigation of the effectiveness of Kampo treatment: At least one course of cancer chemotherapy had been administered; numbness and pain appeared after the chemotherapy; and CIPN was diagnosed before they were given Kampo treatment.

RESULTS

The 24 patients included 6 males and 18 females and ranged in age from 39 to 86 (mean 61.2 ± 11.5) years old. Kampo formulas were individually chosen by Kampo expert doctors based on Kampo-specific diagnostics. Beneficial outcomes were obtained by Kampo treatment in 20 out of the 24 cases (83.3%). Nine out 20 cases had a major response (the numbness and pain showed improvement or reduction by 50% or more), with 7 of 9 cases showing a more than 70% symptom reduction. Eleven out of 20 cases showed a minor response (less than 50% symptom reduction), and 4 out of the 24 cases had no beneficial response. The most frequently used formula was goshajinkigan (GJG), followed by hachimijiogan (HJG) and keishibukuryogan. Thirteen of the 24 cases (54.2%) were prescribed aconite root-containing formulas including GJG and HJG. Aconite root has “warming” effects and ameliorates pain and numbness; 21 out of 24 cases (87.5%) in total used warming formulas such as aconite root-containing formulas to reduce CIPN.

CONCLUSION

Our current study suggested that Kampo formulas chosen based on Kampo-specific diagnostics could be for treating CIPN that is refractory to conventional medicine.

Preventive effect of oral goshajinkigan on chronic oxaliplatin-induced hypoesthesia in rats

Oxaliplatin, a widely used chemotherapeutic agent, induces peripheral neuropathy that manifests itself as two distinct phases: acute cold hyperesthesia and chronic peripheral hypoesthesia/dysesthesia. The latter is a serious dose-limiting side effect that can often lead to withdrawal of treatment. We have developed a rat model expressing both phases and used the model to investigate the action of goshajinkigan (GJG), a traditional Japanese herbal medicine, which was reported to ameliorate oxaliplatin-induced neuropathy in a placebo-controlled double-blind randomized phase II study. In this study, neuropathy was induced by injection of oxaliplatin twice weekly for 8 wks. The maximum level of cold hyperesthesia was observed at 4 wks with heat hypoesthesia developing later. Microscopy studies revealed atrophy of axons of myelinated sciatic nerve fibers in oxaliplatin-treated rats at 8 wks. Co-administration of GJG ameliorated both abnormal sensations as well as histological damage to the sciatic nerve. A pharmacokinetic study revealed numerous neuroprotective components of GJG that are rapidly absorbed into the blood. GJG and some of its components attenuated the generation of oxaliplatin-induced reactive oxygen species, which is a possible mechanism of oxaliplatin-induced neurotoxicity. The present study provides a useful animal model for oxaliplatin-induced neurotoxicity as well as a promising prophylactic agent.

Herbal Medicine Goshajinkigan Prevents Paclitaxel-Induced Mechanical Allodynia without Impairing Antitumor Activity of Paclitaxel

Chemotherapy-induced peripheral neuropathy is a major dose-limiting side effect of commonly used chemotherapeutic agents. However, there are no effective strategies to treat the neuropathy. We examined whether Goshajinkigan, a herbal medicine, would prevent paclitaxel-induced allodynia without affecting the anticancer action in mice. Murine breast cancer 4T1 cells were inoculated into the mammary fat pad. Paclitaxel (10 and 20 mg/kg, intraperitoneal, alternate day from day 7 postinoculation) inhibited the tumor growth, and Goshajinkigan (1 g/kg, oral, daily from day 2 postinoculation) did not affect the antitumor action of paclitaxel. Mechanical allodynia developed in the inoculated region due to tumor growth and in the hind paw due to paclitaxel-induced neuropathy. Paclitaxel-induced allodynia was markedly prevented by Goshajinkigan, although tumor-associated allodynia was not inhibited by Goshajinkigan. These results suggest that Goshajinkigan prevents paclitaxel-induced peripheral neuropathy without interfering with the anti-cancer action of paclitaxel.

Can medical herbs stimulate regeneration or neuroprotection and treat neuropathic pain in chemotherapy-induced peripheral neuropathy?

Chemotherapy-induced neuropathy (CIPN) has a relevant impact on the quality of life of cancer patients. There are no curative conventional treatments, so further options have to be investigated. We conducted a systematic review in English and Chinese language databases to illuminate the role of medical herbs. 26 relevant studies on 5 single herbs, one extract, one receptor-agonist, and 8 combinations of herbs were identified focusing on the single herbs Acorus calamus rhizoma, Cannabis sativa fructus, Chamomilla matricaria, Ginkgo biloba, Salvia officinalis, Sweet bee venom, Fritillaria cirrhosae bulbus, and the herbal combinations Bu Yang Huan Wu, modified Bu Yang Huan Wu plus Liuwei Di Huang, modified Chai Hu Long Gu Mu Li Wan, Geranii herba plus Aconiti lateralis praeparata radix , Niu Che Sen Qi Wan (Goshajinkigan), Gui Zhi Jia Shu Fu Tang (Keishikajutsubuto), Huang Qi Wu Wu Tang (Ogikeishigomotsuto), and Shao Yao Gan Cao Tang (Shakuyakukanzoto). The knowledge of mechanism of action is still limited, the quality of clinical trials needs further improvement, and studies have not yielded enough evidence to establish a standard practice, but a lot of promising substances have been identified. While CIPN has multiple mechanisms of neuronal degeneration, a combination of herbs or substances might deal with multiple targets for the aim of neuroprotection or neuroregeneration in CIPN.

Beneficial effects of Gosha-jinki-gan and green tea extract in rats with chemical cystitis

The aim of this study was to characterize pharmacological effects of gosha-jinki-gan (GJG) and green tea extract (GTE), on urodynamic parameters, bladder receptors, and urinary cytokines in rats with cyclophosphamide (CYP)-induced cystitis. Urodynamic parameters in CYP-treated rats were measured using the cystometric method. Muscarinic and purinergic receptors in rat tissues were measured by radioreceptor assays. Urinary cytokine levels were measured with ELISA kits. GJG and GTE were orally administered to rats once a day for 7 days. The GJG treatment significantly ameliorated changes in urodynamic parameters in CYP-treated rats. Similar treatment with GTE slightly attenuated changes in urodynamic parameters. The maximal number of binding sites for [³H]NMS and [³H]αβ-MeATP in the bladder was significantly lower in CYP-treated rats than in sham rats. Such a reduction in receptor density was significantly attenuated by the GJG treatment. GTE treatment also significantly attenuated the down-regulation of muscarinic receptors, but not P2X receptors in bladders of rats with CYP-induced cystitis. The elevation in urinary cytokine levels in CYP-treated rats was effectively attenuated by GJG treatment. The elevation in cytokine levels in CYP-treated rats was alleviated by GTE treatment. In conclusion, GJG may be a pharmacologically useful plant extract for cystitis.

Goshajinkigan reduces oxaliplatin-induced peripheral neuropathy without affecting anti-tumour efficacy in rodents

Oxaliplatin is a key drug in the treatment of colorectal cancer, but it causes acute and chronic neuropathies in patients. Goshajinkigan (GJG) is a Kampo medicine that is used for the treatments of several neurological symptoms including pain and numbness. More recently, GJG has been reported to prevent the oxaliplatin-induced peripheral neuropathy in clinical studies. No experimental study, however, has been conducted to date to determine the effect of GJG on pain behaviour in a rat model of oxaliplatin-induced neuropathy. Moreover, the impact on the anti-tumour effect of oxaliplatin remains unknown. In the present study, we examined the effects of GJG on the peripheral neuropathy and anti-tumour activity of oxaliplatin in rodents. Repeated administration of oxaliplatin caused cold hyperalgesia from days 3 to 37 and mechanical allodynia from days 21 to 28. Repeated administration of GJG prevented the oxaliplatin-induced cold hyperalgesia but not mechanical allodynia and axonal degeneration in rat sciatic nerve. Single administration of GJG reduced both cold hyperalgesia and mechanical allodynia after the development of neuropathy. In addition, GJG did not affect the anti-tumour effect of oxaliplatin in the tumour cells or tumour cells-implanted mice. These results suggest that GJG relieves the oxaliplatin-induced cold hyperalgesia and mechanical allodynia without affecting anti-tumour activity of oxaliplatin, and, therefore, may be useful for the oxaliplatin-induced neuropathy in clinical practice.

Effect of Mongolian plants on in vivo insulin action in diabetic rats

In the present study, we firstly performed a preliminary investigation on the acute effect of Mongolian medicinal plant extracts (Dryopteris species, Aspidiaceae) on the glucose tolerance in rats, evaluated by an oral glucose tolerance test (OGTT). Then, we investigated the effect of the same extracts on in vivo insulin action in streptozotocin (50 mg kg(-1) BW, i.v.)-induced diabetic rats by means of the euglycemic clamp. In diabetic rats, the glucose metabolic clearance rate (MCR) during 3.0 (low-dose) and 30.0 mU kg(-1)min(-1) (high-dose) insulin infusion was significantly higher in animals administered with plant extracts (500 mg kg(-1) BW, p.o.), compared with saline-administered animals (low-dose--normal control: 16.3+/-0.7 ml kg(-1)min(-1) versus plant extract 1: 15.8+/-0.6 ml kg(-1)min(-1) and plant extract 2: 14.0+/-0.5 ml kg(-1)min(-1), diabetic control: 10.9+/-0.6 ml kg(-1)min(-1) versus plant extract 1: 19.3+/-1.4 ml kg(-1)min(-1) and plant extract 2: 20.5+/-1.5 ml kg(-1)min(-1); high-dose-normal control: 50.9+/-2.6 ml kg(-1)min(-1) versus plant extract 1: 49.8+/-2.6 ml kg(-1)min(-1) and plant extract 2: 48.4+/-2.4 ml kg(-1)min(-1), diabetic control: 26.9+/-1.6 ml kg(-1)min(-1) versus plant extract 1: 33.5+/-1.7 ml kg(-1)min(-1) and plant extract 2: 37.2+/-1.9 ml kg(-1)min(-1); P<0.05, respectively). These results suggest that a single administration of the two Mongolian plant extracts can improve glucose utilization and insulin resistance in diabetic rats.

Maintaining the redox-balance intact: gosha-jinki-gan but not insulin activates retinal soluble guanylate cyclase in diabetic rats

Strategies to prevent hyperglycemia-induced cytotoxic reactive oxygen species in the retina include the prevention of free radical production, activation of radical-scavenging capacities and inhibition of aldose reductase. This study examined the effect of the standardized Japanese herbal extract product gosha-jinki-gan (GJG) in comparison to insulin treatment in the rat retina. Diabetes was induced in male Wistar rats by single injection of streptozotocin (50 mg/kg i.p.). At 6 and 12 weeks, eye-cups were removed for immunohistochemistry. At 12 weeks, lipid peroxidation (tested with the antiacrolein antibody, Ab5F6) was enhanced significantly in the untreated diabetic group. This effect was absent in both treatment groups, notably in the outer retina. A similar result was obtained for nitrotyrosine overproduction. As an early treatment effect, GJG -- but not insulin -- enhanced soluble guanylate cyclase (sGC) activation (using the function-sensing antibody, MoAb 3221). GJG not only reduces nitroxidative stress and lipid peroxidation in the retina, it also ameliorates glucose metabolism within the cells. We propose that the high glucose turnover in the insulin-treated model disturbs the intracellular redox equilibrium, one result of which might be the impaired sGC activation.

Effects of Goshajinkigan on insulin resistance in patients with type 2 diabetes

We investigated the effects of Goshajinkigan (GJG), a Chinese herbal medicine, on insulin sensitivity in patients with type 2 diabetes using the homeostasis model assessment of insulin resistance (HOMA-R) and the euglycemic insulin clamp procedure. Daily oral administration of GJG (7.5 g/day) was performed for 1 month in 71 type 2 diabetes patients: the GJG treatment group. HOMA-Rs were calculated before and after 1 month of GJG treatment and compared with those of 44 controls who were matched in terms of sex, age, body mass index (BMI) and HbA1c levels with the experimental group. In 64 patients out of the GJG treatment group, HOMA-R was calculated 1 month after discontinuation of treatment. In addition, euglycemic clamp was conducted in eight patients before and after the GJG treatment. HOMA-R was 4.78+/-0.37 (means+/-S.E.) before GJG treatment and significantly decreased to 4.02+/-0.25 after GJG treatment (P=0.019). No significant change was observed in the control group. HOMA-R returned to the pre-treatment level (P=0.018) 1 month after GJG treatment discontinuation. Glucose infusion rates and metabolic clearance rates determined by the high-dose euglycemic clamp increased after 1 month of GJG treatment (from 9.6+/-1.1 to 11.1+/-0.7 mg/kg/min, P=0.045 and from 7.9+/-0.8 to 9.1+/-0.8 ml/kg/min, P=0.046, respectively). These results indicate that GJG administration might be useful for improving insulin resistance in patients with type 2 diabetes.

Aconiti tuber increases plasma nitrite and nitrate levels in humans

Some herbal medicines, including Aconiti tuber (Aconitum carmichaeli Debeaux, Ranunculaceae), have been recognized as being effective for the treatment of a "peripheral uncomfortable feeling of cold (hie)". We hypothesized that these compounds affect peripheral vascular function via the nitric oxide (NO) system, which leads to recovery from "hie". To answer this question, we investigated Aconiti tuber-induced changes in plasma levels of nitrite (p-NO2-) and nitrate (p-NO3-), final nitric oxide-oxidation products measurable in vivo. After written informed consent was obtained, patients suffering from "hie" were treated with several kinds of kampo (Japanese traditional herbal medicine), selected on the basis of traditional theory. Twenty-four patients took kampo formulas, some included Aconiti tuber (n=11; A-group) and others did not (n=13; C-group), for 4 weeks. p-NO2- and p-NO3- levels were measured before the start and after 4 weeks of treatment. In the A-group, the p-NO2- plus p-NO3- (p-NOx) level was significantly increased at 4 weeks (p=0.04), while that of the C-group was not. There was a statistically significant increase in the p-NOx level of the A-group as compared to the C-group (d.f.=1,22, F=9.38, p=0.006). The results suggest that Aconiti tuber may increase NO production in humans.

Gosha-jinki-gan (a Herbal Complex) Corrects Abnormal Insulin Signaling

Previous studies have shown that the traditional herbal complex Gosha-jinki-gan (GJG) improves diabetic neuropathy and insulin resistance. The present study was undertaken to elucidate the molecular mechanisms related with the long-term effects of GJG administration on insulin action in vivo and the early steps of insulin signaling in skeletal muscle in streptozotocin (STZ) diabetes. Rats were randomized into five subgroups: (1) saline treated control, (2) GJG treated control, (3) 2-unit insulin + saline treated diabetic, (4) saline + GJG treated diabetic and (5) 2-unit insulin + GJG treated diabetic groups. After seven days of treatment, euglycemic clamp experiment at an insulin infusion rate of 6 mU/kg/min was performed in overnight fasted rats. Despite the 2-unit insulin treatment, the metabolic clearance rates of glucose (MCR, ml/kg/min) in diabetic rats were significantly lower compared with the controls (11.4 +/- 1.0 vs 44.1 +/- 1.5; P < 0.001), and were significantly improved by insulin combined with GJG or GJG alone (26 +/- 3.2 and 24.6 +/- 2.2, P < 0.01, respectively). The increased insulin receptor (IR)-beta protein content in skeletal muscle of diabetic rats was not affected by insulin combined with GJG administration. However, the decreased insulin receptor substrate-1 (IRS-1) protein content was significantly improved by treatment with GJG. Additionally, the increased tyrosine phosphorylation levels of IR-beta and IRS-1 were significantly inhibited in insulin combined with GJG treated diabetes. The present results suggest that the improvement of the impaired insulin sensitivity in STZ-diabetic rats by administration of GJG may be due, at least in part, to correction in the abnormal early steps of insulin signaling in skeletal muscle.

Effect of Gosha-jinki-gan (Chinese herbal medicine: Niu-Che-Sen-Qi-Wan) on insulin resistance in streptozotocin-induced diabetic rats

Gosha-jinki-gan (GJG) is a Chinese herbal medicine that is known to be useful for the treatment of diabetic neuropathy. In the present study, the effect of GJG on insulin resistance in streptozotocin (STZ, 50 mgkg(-1) BW, i.v.) -induced diabetic rats was examined by means of the euglycemic clamp procedure. To accomplish this objective, diabetic and non-diabetic control rats were divided as follows: a single dose administration of GJG (800 mgkg(-1) BW, p.o.), saline (5 mlkg(-1) BW, p.o.), and GJG (p.o)+N(G)-monomethyl-L-arginine (L-NMMA, 1 mgkg(-1)min(-1) BW, i.v.). In diabetic rats, the incremental area (DeltaAUC [area under curve]) of the glucose metabolic clearance rate (MCR) during a 3.0 mUkg(-1)min(-1) insulin infusion rate was significantly higher in the GJG-administrated group compared to the saline-administrated one. On the other hand, the effect of GJG on the DeltaAUC of MCR in diabetic rats was abolished by L-NMMA. In addition, no significant differences in the DeltaAUC of MCR were observed in non-diabetic control rats. These results suggest that a single dose administration of GJG can improve the glucose utilization and insulin resistance in STZ-induced diabetic rats, probably via the nitric oxide (NO) pathway.

Antinociceptive mechanism of Gosha-jinki-gan in streptozotocin-induced diabetic animals: role of nitric oxide in the periphery

Using streptozotocin-induced diabetic mice and rats, we evaluated the antinociceptive mechanism of Gosha-jinki-gan. The antinociceptive effect of Gosha-jinki-gan (0.3 g/kg, p.o.) in diabetic mice, as determined by the tail-pressure test, was inhibited by N(G)-nitro-L-arginine methyl ester (L-NAME; 2, 5 mg/kg, i.p.). When L-NAME (10 microg) or methylene blue (500 microg) was topically administered to the intraplantar area of the hind paw, the region used for the paw-pressure test, the antinociceptive activity of Gosha-jinki-gan (0.3 g/kg, p.o.) in diabetic rats was decreased. These results suggested that the antinociceptive effect of Gosha-jinki-gan partly resulted from the peripheral action of increasingly produced nitric oxide.

Antinociceptive effect of Gosha-jinki-gan, a Kampo medicine, in streptozotocin-induced diabetic mice

We evaluated the antinociceptive effect of Gosha-jinki-gan, a Kampo medicine including processed Aconiti tuber, and its mechanism in streptozotocin-induced diabetic mice. Gosha-jinki-gan (0.1-1.0 g/kg, p.o.) showed a more potent antinociceptive effect in diabetic mice than in non-diabetic mice. The antinociceptive effect of Gosha-jinki-gan (0.3 g/kg, p.o.) in diabetic mice was inhibited by administration of either anti-dynorphin antiserum (5 microg, i.t.) or nor-binaltorphimine (10 mg/kg, s.c.), a kappa-opioid antagonist. The antinociceptive activity of Gosha-jinki-gan (0.3, 1.0 g/kg, p.o.) was decreased by excluding processed Aconiti tuber. Furthermore, the antinociceptive effect of processed Aconiti tuber (0.03, 0.1 g/kg, p.o.) was also shown to be enhanced in diabetic mice. These results suggest that the increased antinociceptive effect of Gosha-jinki-gan in diabetic mice is partly derived from the action of processed Aconiti tuber and that it is based on stimulation of spinal kappa-opioid receptors via dynorphin release. Gosha-jinki-gan was considered useful for treating painful diabetic neuropathy.

Effect of Gosha-jinki-gan, a Kampo medicine, on enhanced platelet aggregation in streptozotocin-induced diabetic rats

We evaluated the effects of Gosha-jinki-gan on platelet aggregation in streptozotocin-induced diabetic rats. Enhanced ADP (2 microM)-induced aggregation of platelets obtained from diabetic rats was inhibited by a single treatment with Gosha-jinki-gan (0.3, 1.5 g/kg, p.o.). The anti-platelet aggregatory effect of Gosha-jinki-gan (1.5 g/kg, p.o.) was attenuated by simultaneous administration of atropine (1 mg/kg, i.p.) and was abolished by combination of atropine with Hoe 140 (250 microg/kg x 2, i.p.), a bradykinin B2 receptor antagonist or L-NAME (10 mg/kg, i.p.), an inhibitor of nitric oxide-synthase. These results suggested that Gosha-jinki-gan could improve platelet aggregation in diabetes through increased production of nitric oxide via bradykinin B2-receptors and muscarinic acetylcholine receptors.