Biomedical subjects

N Murakami

Publications and source records attributed to N Murakami.

At least 163 records · Page 9Linked to original sources

PubMed1997

Relationship between respiratory failure and plasma noradrenaline levels in amyotrophic lateral sclerosis.

We evaluated plasma noradrenaline (NA) levels at test and during head-up tilt test in 20 patients with sporadic amyotrophic lateral sclerosis (ALS). Their fasting plasma NA levels ranged from 195 to 4227 pg/ml. The average plasma NA level was 483 pg/ml in five ambulatory patients, 341 in two wheelchair-bound patients, 1264 in 11 bedridden patients, and 208 in two respirator-dependent patients whose disability grading was the worst among the four groups. Arterial carbon dioxide (PCO2) was evaluated as a measure of respiratory function. The coefficient of correlation between PCO2 and plasma NA was r = 0.654 (p < 0.01). Either respiratory failure or lower motor neuron dysfunction may relate to the elevation of plasma NA levels. In the two bedridden patients, plasma NA levels and heart rate at rest increased significantly as the disease progressed. Cardiovascular responses to head-up tilting were normal. These data suggest that the elevation of plasma NA levels may be related to progression of respiratory failure and lower motor neuron dysfunction. In conclusion, sympathetic hyperactivity in ALS is considered to be not primary, but secondary to somatic motor disabilities and respiratory failure.

Aged↗

PubMed1997

Thyroid cancer associated with adenomatous goiter: an analysis of the incidence and clinical factors.

We evaluated the incidence of thyroid cancer in patients with adenomatous goiter and investigated the clinical factors distinguishing patients with occult thyroid cancer, defined as a tumor size smaller than or equal to 10 mm, from those with clinical thyroid cancer, defined as a tumor size larger than 10 mm. Of 835 patients with histologically confirmed adenomatous goiter, 256 (30.7%) also had thyroid cancer, being occult in 137 patients and clinical in 119 patients. There was no correlation between the maximum size of the thyroid cancer tumor and the age of the patient, and the percentage of patients with thyroid cancer in each group was not influenced by age. There were no significant differences in age, sex, the serum concentrations of free triiodothyronine, free thyroxine, thyrotropin, and thyroglobulin, or the urinary iodine creatinine ratio. The frequency of calcified lesions being detected by ultrasonography (US) and/or neck X-ray in the patients with clinical thyroid cancer was significantly greater than that in those with occult cancer at 83% vs 57%, respectively (P < 0.0001). This study disclosed a high prevalence of thyroid cancer associated with adenomatous goiter, and the results suggest that a considerable number of associated carcinomas remain occult. The detection of calcification in the thyroid gland is one of the surgical indications for patients with adenomatous goiter.

Adenocarcinoma, Follicular↗

PubMed1997

Apoptotic nuclear degeneration in Marinesco-Sjögren syndrome.

In 12 patients with the clinical characteristics of Marinesco-Sjögren syndrome including an autosomal recessive inheritance, congenital cataracts, mental retardation, cerebellar ataxia and progressive muscle weakness, the most common pathological finding was rimmed vacuole formation comprising from 0.1% to 10% of fibers in their muscle biopsy samples. The nuclear changes varied from condensed chromatin granules to vacuolation with amorphous inclusions which were predominantly seen in younger patients with prominent rimmed vacuoles, suggesting a close relationship between nuclear change and rimmed vacuole formation. From the severe destructive changes in nuclei, we speculated that the nuclear changes in Marinesco-Sjögren syndrome play a primary role in muscle degeneration resulting in myofibrillar disorganization and rimmed vacuole formation. In 2 patients, the TUNEL method demonstrated scattered myonuclei with fragmented DNA, but "ladder formation" was not found, probably because of the small numbers of nuclei with fragmented DNA. Nuclear degeneration with focal myofibrillar degeneration seen in these muscle samples suggests that the apoptotic process may occur in muscle disorders, especially in diseases with rimmed vacuole formation.

Adult↗

PubMed1997

Differential expression of nonmuscle myosin II isoforms in human atherosclerotic plaque.

Intimal proliferation and functional changes involving vascular smooth muscle cells are key events in the development of atherosclerosis, including restenosis after percutaneous transluminal angioplasty. Nonmuscle myosin (NMM) is required for cytokinesis and has been shown in cultures of vascular smooth muscle cells to undergo changes of isoform expression depending on the stage of proliferation and differentiation. The purpose of this study was to examine the differential expression of the two most recently identified nonmuscle myosin heavy chain isoform II (NMMHC-II) isoforms A and B in atherosclerotic plaque. Primary atherosclerotic and restenotic atherectomy specimens and non-atherosclerotic controls, were analyzed by Western Blot analysis, immunohistochemistry and in situ hybridization. Nonmuscle myosin heavy chain isoform IIA (NMMHC-IIA) was equally expressed in all types of tissue specimens both at the protein and mRNA levels. In contrast, NMMHC-IIB protein was found in restenotic specimens and normal artery but was at very low levels in primary atherosclerotic plaque. By in situ hybridization NMMHC-IIB mRNA levels were significantly greater in restenotic versus primary atherosclerotic lesions. NMMHC-IIB expression is associated with vascular restenosis but is downregulated in stable atherosclerotic lesions, whereas NMMHC-IIA is expressed in both. These results indicate that these new myosin isoforms have different functions and should be regarded separately with respect to smooth muscle proliferation and restenosis. They should prove to be useful molecular markers for the study of atherosclerosis and restenosis.

Aged↗

PubMed1997

Muscle histopathology in diabetes mellitus associated with mitochondrial tRNA(Leu(UUR)) mutation at position 3243.

Diabetes mellitus associated with 3243 mitochondrial tRNA(Leu(UUR)) mutation (DM-Mt3243) is a subtype of the mitochondrial multisystem syndromes, usually lacking myopathy. Muscle biopsies were obtained from 5 patients with diabetes and one patient with impaired glucose tolerance, all possessing the 3243 mutation without hallmarks of MELAS. The specimens were subjected to histochemical, biochemical, and genetic analysis. Ragged-red fibers were seen in 4 of the 6 patients (67%), and focal cytochrome c oxidase deficiency in 3 (50%). Strongly succinate dehydrogenase-reactive blood vessels was found in 5 patients (83%). The histochemical signs were present even when the mutant percentage was very low. The percentage of mutant DNA was almost always higher in muscles than in leukocytes. The combination of allele specific PCR amplification and PCR-RFLP method was useful to evaluate the mutant proportion. The mutant percentage in muscle was under 50% in 5 (83%) patients. Mitochondrial enzyme activity was deficient only in one patient. This study presents the detailed muscle histopathology in the DM-Mt3243 group. Abnormal histopathologic findings seemed similar to those noted in MELAS. However, mutant percentage in muscles was lower than that of MELAS, and respiratory chain enzyme activity was well preserved.

Acidosis, Lactic↗

PubMed1997

Antihyperglycemic mechanism of M16209, an antidiabetic agent, in 3T3-L1 adipocytes.

We investigated the effect of M16209 (1-(3-bromobenzo[b]furan-2-ylsulfonyl)hydantoin) on glucose transport and the insulin signaling system in mouse-derived 3T3-L1 adipocytes. When M16209 (30 and 100 microM) was added to 3T3-L1 adipocytes and preincubated for 24 hours, the uptake of 2-deoxy-D-[3H]-glucose (2-DG) after insulin stimulation was enhanced. This effect was seen when preincubation with M16209 was performed in the presence of 6 and 20 ng/ml insulin, but M16209 did not increase the response to 600 ng/ml insulin. M16209 (100 microM) did not interfere with (125)I-insulin binding or with tyrosine phosphorylation of the insulin receptor beta-subunit and IRS-1. M16209 (100 microM) also had no effect on the level of glucose transporter (GLUT1 and GLUT4) protein, but it promoted the translocation of intracellular GLUT4 to the plasma membrane. In contrast, M16209 had no effect on the translocation of GLUT1. In summary, M16209 enhanced 2-DG uptake by 3T3-L1 adipocytes. Insulin binding to its receptor, autophosphorylation of the insulin receptor beta-subunit, and tyrosine phosphorylation of IRS-1 were unaffected by M16209. However, translocation of GLUT4 from the intracellular pool to the plasma membrane was facilitated.

3T3 Cells↗

PubMed1997

Daily wheel running activity modifies the period of free-running rhythm in rats via intergeniculate leaflet.

The period of free-running rhythms (tau) in rats, as measured using a running wheel, is different from that measured using an Automex. The aim of this work was to examine the effects of lesions of the intergeniculate leaflet (IGL) on the tau of these two activity rhythms. When blind rats were transferred from a cage with a running wheel to a cage without a running wheel, the tau lengthened. The tau of the wheel-running activity was associated with the number of wheel revolutions per day. A complete lesion of the IGL lengthened the tau of the wheel-running activity, and caused a reduction in the number of wheel revolutions per day in all rats. In rats housed in cages without a running wheel, locomotor activity was reduced by IGL lesions, although the tau was unaffected. When IGL-lesioned rats were transferred from a cage with a running wheel to a cage without a running wheel, no further change was observed. These results indicate that the tau is modified by the daily activity of wheel-running, but not by general locomotor activity, and that the IGL may be involved in this modification.

Animals↗

PubMed1997

Postoperative tetany in patients with Graves' disease: a risk factor analysis.

OBJECTIVE: There is little information regarding the clinical risk factors for postoperative tetany in patients with Graves' disease. We analysed the risk factors responsible for postoperative tetany by univariate and multivariate analysis in thyroidectomized patients with Graves' disease, and we discuss the mechanisms of hypocalcaemia and tetany after surgery. PATIENTS: The subjects were 1742 consecutive patients with Graves' disease who underwent subtotal thyroidectomy between 1992 and 1994. RESULTS: Univariate analysis of 15 possible risk factors demonstrated that 10 were significant: sex, required operation time, blood loss, preoperative serum calcium level, estimated weight of thyroid remnant, size of goitre, amount of excised thyroid tissue, serum alkaline phosphatase concentration, age at operation and TSH-binding inhibitory immunoglobin (TBII). In multivariate analysis in female patients, the risk factors were: preoperative lower serum calcium level, younger age, higher serum alkaline phosphatase concentration, larger size of goitre and higher value of TBII, in order of decreasing probability of significance. CONCLUSION: These results, combined with previous observations in which a significant decline in serum parathyroid hormone level was found in patients with Graves' disease who suffered postoperative tetany, suggests that postoperative tetany may occur during the period of bone restoration due to antithyroid drug therapy and be due to continuation of a calcium flux bone concomitant with transient hypoparathyroidism induced by surgery. Calcium supplements during preoperative period and/or after surgery may be appropriate for patients who are anticipated to develop postoperative tetany based on these risk factors.

Adolescent↗

PubMed1997

Usefulness of granulocyte count measurement four hours after injection of granulocyte colony-stimulating factor for detecting recovery from antithyroid drug-induced granulocytopenia.

This prospective study was designed to investigate the usefulness of granulocyte count measurements 4 hours after injection of granulocyte colony-stimulating factor (G-CSF) for detecting recovery from antithyroid drug (ATD)-induced granulocytopenia or agranulocytosis. Granulocyte and white blood cell counts were measured 4 hours and 24 hours after patients with ATD-induced granulocytopenia had been given an injection of 75 micrograms of G-CSF (1.1 to 1.9 micrograms/kg; 1.5 +/- 0.2 micrograms/kg [mean +/- standard deviation]). Thirty-seven patients were studied and divided into three groups based on their initial granulocytopenic granulocyte count: 28 with mild (granulocyte count 0.501 to 1.0 x 10(9)/L), 6 with moderate (granulocyte count 0.101 to 0.5 x 10(9)/L), and 3 with severe (granulocyte count less than 0.1 x 10(9)/L) ATD-induced granulocytopenia. Twenty-five of the 28 patients with mild granulocytopenia and 4 of the 6 patients with moderate granulocytopenia were found to have recovered from the granulocytopenia both 4 hours and 24 hours after injection, and their granulocyte counts remained normal thereafter. However, the other 3 patients with mild granulocytopenia, 2 patients with moderate granulocytopenia, and all 3 patients with severe granulocytopenia had not recovered by either 4 or 24 hours after the G-CSF injection. Despite daily G-CSF injections, the granulocyte continued to decrease in most cases. It took 2 to 11 days for these counts to recover from granulocytopenia. These results indicate that granulocyte count measurement 4 hours after injection of G-CSF is useful for detecting recovery from ATD-induced granulocytopenia or agranulocytosis and for predicting disease severity. Accordingly, its measurement enables physicians to make an appropriate decision about whether a patient with ATD-induced granulocytopenia should be treated in the hospital or in the outpatient clinic.

Adolescent↗

PubMed1997

Therapeutic and imaging capacity of tumor-localizing radiosensitive Mn-porphyrin on SCCVII tumor-bearing C3H/He mice.

We synthesized a radiosensitizer KADTF, consisting of a hypoxic radiosensitizer, KU2280, bound to the side chain group of Mn-metalloporphyrin, which accumulates in tumor tissue. In the in vitro colony-forming activity test using HeLa cells, KADTF enhanced the effect of radiation under hypoxic conditions. Radiation therapy at 20 Gy, 1.5 h after infusion of KADTF (0.15 mM/kg), inhibited tumor growth more markedly than did a single radiation treatment. A clear tumor MR images of the SCCVII tumor was obtained at 1.5 h after administration of KADTF (0.1 mM/kg).

Animals↗

PubMed1997

Investigation of morphological change of lateral and midline fluid percussion injury in rats, using magnetic resonance imaging.

OBJECTIVE: Investigating the time course of morphological changes in experimental traumatic brain injury (TBI) in vivo helps to clarify the mechanism of TBI and develop new therapeutic modalities. We examined the morphological changes in experimental TBI, using magnetic resonance imaging (MRI) in a rat model. METHODS: We produced lateral fluid percussion injury (LFP) and midline fluid percussion injury (MFP) in rats, using the Yamaki fluid percussion device. The rats were divided into four groups: LFP, MFP, sham LFP, and sham MFP. MRI was performed with a 4.7-T magnetic resonance apparatus 2 days and 90 days after the induction of injury. T1-, T2-, and T2- weighted images were obtained using a surface coil. RESULTS: Hemorrhage, contusion, and brain edema in LFP models were detected on the 2nd day after injury, and the necrotic tissue was absorbed and replaced by cerebrospinal fluid on the 90th day. In MFP animals, we detected a small hemorrhage in the corpus callosum with minimal brain edema around the hemorrhage on the 2nd day after injury, and on the 90th day, enlarged ventricles and cisterns were observed, indicating brain atrophy. CONCLUSION: MRI, therefore, is useful for plotting morphological changes in experimental TBI in vivo. We report the novel and clinically important finding of brain atrophy after experimental TBI.

Animals↗

PubMed1997

Involvement of protein kinase A in the subjective nocturnal rise of melatonin release by chick pineal cells in constant darkness.

Melatonin release by chick cultured pineal cells increases during the dark periods and decreases during the light periods under light-dark cycles, and this rhythmic secretion is maintained under constant conditions with a period of almost 24 hr. The mechanisms by which the circadian oscillator drives the melatonin rhythm under constant conditions have not been elucidated enough. We examined the possibility that cyclic AMP-dependent protein kinase A is involved in the subjective nocturnal increase in melatonin release by chick pineal cells cultured under constant darkness. The subjective nocturnal increase of melatonin release was suppressed dose dependently by H8 (protein kinase inhibitor) and H89 (specific protein kinase A inhibitor), but not by calphostin C (specific protein kinase C inhibitor) in static cell cultures. In a cell perfusion experiment, 9 hr pulses of H8 and H89 starting at ZT 9 (CT 11.2) hr suppressed the subjective nocturnal increase in melatonin rhythm in dose-dependent manner without causing a phase shift. An intracellular Ca2+ chelator, O,O'-bis(2-aminophenoxy)ethyleneglycol-N,N,N',N'-tetraacetic acid tetraacetoxymethyl ester (BAPTA-AM), and extracellular Ca2+ chelators, O,O'-bis(2-aminophenoxy)ethyleneglycol-N,N,N',N'-tetraacetic acid tetrapotassium salt hydrate (BAPTA) and ethyleneglycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA), suppressed both the subjective nocturnal increases in melatonin release and cAMP levels dose dependently. This direct evidence strongly supports the hypothesis that cAMP-dependent protein kinase A may be involved in the subjective nocturnal increase in melatonin release by chick pineal cells and that intracellular Ca2+ plays an important role in pineal adenylate cyclase activation.

Animals↗

PubMed1997

Gadolinium-enhanced MR imaging of thyroid and parathyroid masses.

PURPOSE: To evaluate spin-echo and contrast material-enhanced dynamic magnetic resonance (MR) imaging in characterization of thyroid and parathyroid masses. MATERIALS AND METHODS: Conventional T1- and T2-weighted, gadolinium-enhanced dynamic, and gadolinium-enhanced T1-weighted spin-echo imaging sequences were performed in 85 patients with thyroid and parathyroid tumors. Findings from spin-echo imaging and dynamic curve patterns from mean signal intensity ratios were evaluated for each histologic tumor type. RESULTS: T1- and T2-weighted imaging did not enable differentiation of benign from malignant tumors. Primary thyroid lymphoma enhanced less than other solid thyroid tumors, and parathyroid adenoma also enhanced less than other tumors (P < .05 compared with papillary carcinoma. CONCLUSION: Gadolinium-enhanced MR imaging cannot enable prediction of histologic type in thyroid and parathyroid tumors. However, in cases of multiple tumors, the technique may improve the contrast between the different histologic types and sometimes suggest the diagnosis of primary thyroid lymphoma or parathyroid adenoma.

Adenoma↗

PubMed1997

Bioactive saponins and glycosides. VIII. Notoginseng (1): new dammarane-type triterpene oligoglycosides, notoginsenosides-A, -B, -C, and -D, from the dried root of Panax notoginseng (Burk.) F.H. Chen.

The glycosidic fraction from the dried roots of Panax notoginseng (Burk.) F.H. Chen was found to show protective effect on liver injury induced by D-galactosamine and lipopolysaccharide. From the glycosidic fraction with hepatoprotective effect, nine new dammarane-type triterpene oligoglycosides, notoginsenosides-A, -B, -C, -D, -E, -G, -H, -I, and -J and an acetylenic fatty acid glycoside, notoginsenic acid beta-sophoroside, were isolated together with fourteen known dammarane-type triterpene oligoglycosides. The structures of notoginsenosides-A, -B, -C and -D were determined on the basis of chemical and physicochemical evidence, which included the chemical correlation with ginsenoside-Rb1 using photosensitized oxygenation, as follows: notoginsenoside A; 3-O-[beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl] 3 beta, 12 beta,20(S),25-tetrahydroxydammar -23-ene; B; 3-O-[beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-glucopyranosyl (1-->6)-beta-D- glucopyranosyl] 3 beta, 12 beta,20(S)-trihydroxydammar-25-en-24-one, C; 3-O-[beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D -glucopyranosyl (1-->6)-beta-D-glucopyranosyl] 3 beta,12 beta,20(S)- trihydroxy-24 zeta-hydroperoxydammar-25-ene, and D; 3-O-[beta-D-xylopyranosyl (1-->2)-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-xylopyranosyl (1-->6)-beta-D-glucopyranosyl (1-->6)-beta-D-glucopyranosyl]20(S)-protopanaxadiol, respectively.

Animals↗

PubMed1997

Bioactive saponins and glycosides. X. On the constituents of zizyphi spinosi semen, the seeds of Zizyphus jujuba Mill. var. spinosa Hu (1): structures and histamine release-inhibitory effect of jujubosides A1 and C and acetyljujuboside B.

New dammarane-type triterpene oligoglycosides, jujubosides A1 and C and acetyljujuboside B1 were isolated from Zizyphi Spinosi Semen, the seeds of Zizyphus jujuba MILL. var. spinosa Hu, together-with three known saponins. The structures of jujubosides A1 and C and acetyljujuboside B were determined on the basis of chemical and physicochemical evidence. Jujubosides A1 and C and acetyljujuboside B were found to inhibit the histamine release from rat peritoneal exudate cells induced by antigen-antibody-reaction.

Animals↗

PubMed1997

Medicinal foodstuffs. IX. The inhibitors of glucose absorption from the leaves of Gymnema sylvestre R. BR. (Asclepiadaceae): structures of gymnemosides a and b.

Although the glycosidic fraction from the dried leaves of Gymnema sylvestre R. BR., gymnemic acid, was reported to be effective for diabetes, it showed little inhibitory activity on the increase of serum glucose level in oral glucose-loaded rats. From the glycosidic fraction, six triterpene glycosides, gymnemosides a, b, c, d, e, and f, were isolated together with nine known triterpene glycosides. The structures of gymnemosides a and b were determined on the basis of chemical and physicochemical evidence as 21-O-tigloyl-22-O-acetylgymnemagenin 3-O-beta-D-glucopyranosiduronic acid and 16-O-acetyl-21-O-tigloylgymnemagenin 3-O-beta-D-glucopyranosiduronic acid, respectively. In addition, an acetyl group linked to the 16- or 22-hydroxyl group in gymnemosides a and b was found to migrate easily to the primary 28-hydroxyl group, while the acyl migration from the 28-position was rarely observed. The inhibitory activity of each triterpene glycoside from gymnemic acid was examined to determine its impact on the increase of serum glucose level in oral glucose-loaded rats. Gymnemoside b and gymnemic acids III, V, and VII were found to exhibit a little inhibitory activity against glucose absorption, but the principal constituents, gymnemic acid I and gymnemasaponin V, lacked this activity.

Animals↗

PubMed1997

Medicinal foodstuffs. IV. Fenugreek seed. (1): structures of trigoneosides Ia, Ib, IIa, IIb, IIIa, and IIIb, new furostanol saponins from the seeds of Indian Trigonella foenum-graecum L.

Six new furostanol saponins called trigoneosides Ia, Ib, IIa, IIb, IIIa, and IIIb were isolated from a medicinal foodstuff, fenugreek seed, the seed of Trigonella foenum-graecum L. (Leguminosae) originating from India, together with two known saponins, glycoside D and trigofoenoside A. The structures of trigoneosides Ia, Ib, IIa, IIb, IIIa, and IIIb were determined on the basis of chemical and physicochemical evidence as 26-O-beta-D-glucopyranosyl-(25S)-5 alpha-furostane-2 alpha,3 beta,22 zeta,26-tetraol 3-O-[beta-D-xylopyranosyl (1 --> 6)]-beta-D-glucopyranoside, 26-O-beta-D-glucopyranosyl-(25R)- 5 alpha-furostane-2 alpha,3 beta,22 zeta,26-tetraol 3-O-[beta-D-xylopyranosyl (1-->6)]-beta-D-glucopyranoside, 26-O-beta-D-glucopyranosyl-(25R)-5 beta-furostane-3 beta,22 zeta,26-triol 3-O-[beta-D-xylopyranosyl (1 --> 6)]-beta-D-glucopyranoside, 26-O-beta-D-glucopyranosyl-(25R)-5 beta-furostane-3 beta,22 zeta,26-triol 3-O-[beta-D-xylopyranosyl (1-->6)]-beta-D-glucopyranoside, 26-O-beta-D-glucopyranosyl-(25S)-5 alpha-furostane-3 beta,22 zeta,26-triol 3-O-[alpha-L-rhamnopyranosyl(1 --> 2)]-beta-D-glucopyranoside, and 26-O-beta-D-glucopyranosyl-(25R)-5 alpha-furostane-3 beta,22 zeta,26-triol 3-O-[alpha-L-rhamnopyranosyl (1 --> 2)]-beta-D-glucopyranoside, respectively.

India↗

PubMed1997

[Bioactive constituents of Chinese natural medicines. III. Absolute stereostructures of new dihydroflavonols, hovenitins I, II, and III, isolated from hoveniae semen seu fructus, the seed and fruit of Hovenia dulcis THUNB. (Rhamnaceae): inhibitory effect on alcohol-induced muscular relaxation and hepatoprotective activity].

The methanol-soluble fraction from a Chinese natural medicine Hoveniae Semen Seu Fructus, the seed and fruit of Hovenia dulcis THUNB. (Rhamnaceae) was found to show an inhibitory effect on the alcohol-induced muscular relaxation and a protective activity on the D-galactosamine/lipopolysaccharide or carbon tetrachloride-induced liver injury. Through bioassay-guided separation using a traction performance test, three new dihydrofravonols named hovenitins I, II, and III were isolated from Hoveniae Semen Seu Fructus together with four known flavonoids, (+)-ampelopsin, laricetrin, myricetin, and (+)-gallocatechin. The absolute stereostructures of hovenitins I, II, and III were determined on the basis of chemical and physicochemical evidence to be (2R, 3R)-5,7,4',5'-tetrahydroxy-3'-methoxydihydroflavonol, (2R,3S)-5,7,4',5'-tetrahydroxy-3'-methoxy-dihydroflavonol, and (2R, 3S)-5,7,3',4',5'-pentahydroxydihydro-flavonol, respectively. Hovenitin I and (+)-ampelopsin, both of which were principal ingredients of the active fractions from this natural medicine, were found to show an inhibitory activity on the ethanol-induced muscle relaxation in rats. In addition, hovenitin I showed a protective activity on the liver injury induced by D-galactosamine/lipopolysaccharide or carbon tetrachloride in mice.

Animals↗