Mevalonate kinase in lysates of cultured human fibroblasts and lymphoblasts: kinetic properties, assay conditions, carrier detection and measurement of residual activity in a patient with mevalonic aciduria

An assay has been developed for the measurement of mevalonate kinase activity in extracts of cultured human fibroblasts and lymphoblasts. Individual elements of the assay were investigated in order to achieve optimum conditions. Apparent Michaelis constants (KMapp) for the substrates mevalonic acid and adenosine-5'-triphosphate were 22 +/- 10 mumol/l and 0.42-0.53 mmol/l, respectively, in lysates of control fibroblast lines. The same values in lysates of a control lymphoblast line were 17 mumol/l and 0.23 mmol/l, respectively. Mevalonate kinase activity in extracts of cultured fibroblasts derived from 6 control individuals was 3.24 +/- (SD) 0.91 nmol/min/mg protein. The activity in extracts of fibroblasts derived from a patient with mevalonic aciduria was 0.15 +/- 0.10 nmol/min/mg protein, approximately 5% of the control mean. The parents and brother of the patient displayed mevalonate kinase activities in fibroblast extracts approximating 38-42% of the control mean. Substantially higher mevalonate kinase activity was documented in extracts of cultured lymphoblasts. When assayed on various occasions, the mean activity of mevalonate kinase in extracts of lymphoblasts derived from the parents, brother and maternal grandmother of the patient ranged from 27 to 32% of the mean activity of 9.8 +/- (SD) 3.4 nmol/min/mg protein measured in a parallel control lymphoblast line, while the mean activity in a maternal and paternal uncle approximated 65-89% of the same control mean. The mean activity in extracts of lymphoblasts derived from the patient approximated 2% of the control mean. The data suggest that the parents, brother and maternal grandmother are carriers of the defective gene responsible for mevalonate kinase deficiency, consistent with an autosomal recessive mode of inheritance.     

Efficient in vitro regeneration of fertile plants from corm explants of Hypoxis hemerocallidea landrace Gaza—The “African Potato”

We present efficient protocols for the regeneration of fertile plants from corm explants of Hypoxis hemerocallidea Fisch. & C. A. Mey. landrace Gaza, either by direct multiple shoot formation or via shoot organogenesis from corm-derived calluses. The regeneration efficiency depended on plant growth regulator concentrations and combinations. Multiple direct shoot formation with high frequency (100% with 5–8 shoots/explant) was obtained on a basal medium (BM) supplemented with 3 mg/l kinetin (BM1). However, efficient indirect regeneration occurred when corm explants were first plated on callus induction medium (BM2) with high kinetin (3 mg/l) and naphthalene acetic acid (NAA 1 mg/l), and then transferred to shoot inducing medium (BM3) containing BA (1.5 mg/l) and NAA (0.5 mg/l). Shoot regeneration frequency was 100% and 30–35 shoots per explant were obtained. The regenerated shoots were rooted on a root inducing medium (BM4) containing NAA (0.1 mg/l). Rooted plantlets were transferred to the greenhouse. The regenerants were morphologically normal and fertile. Flow cytometric analyses and chloroplast counts of guard cells suggested that the regenerants were diploid. Efficient cloning protocols described here, have the potential not only to substantially reduce the pressure on natural populations but also for wider biotechnological applications of Hypoxis hemerocallidea—an endangered medicinal plant.     

Repression of Pseudomonas putida phenanthrene-degrading activity by plant root extracts and exudates

The phenanthrene-degrading activity (PDA) of Pseudomonas putida ATCC 17484 was repressed after incubation with plant root extracts of oat (Avena sativa), osage orange (Maclura pomifera), hybrid willow (Salix alba x matsudana), kou (Cordia subcordata) and milo (Thespesia populnea) and plant root exudates of oat (Avena sativa) and hybrid poplar (Populus deltoides x nigra DN34). Total organic carbon content of root extracts ranged from 103 to 395 mg l(-1). Characterization of root extracts identified acetate (not detectable to 8.0 mg l(-1)), amino acids (1.7-17.3 mg l(-1)) and glucose (1.6-14.0 mg l(-1)), indicating a complex mixture of substrates. Repression was also observed after exposure to potential root-derived substrates, including organic acids, glucose (carbohydrate) and glutamate (amino acid). Carbon source regulation (e.g. catabolite repression) was apparently responsible for the observed repression of P. putida PDA by root extracts. However, we showed that P. putida grows on root extracts and exudates as sole carbon and energy sources. Enhanced growth on root products may compensate for partial repression, because larger microbial populations are conducive to faster degradation rates. This would explain the commonly reported increase in phenanthrene removal in the rhizosphere.     

Suppression of ethanol and lipopolysaccharide-induced liver injury by extracts of Hydrangeae Dulcis Folium in rats

In female SD rats that were injected with 4 g/kg BW ethanol p.o. followed by a 5 mg/kg BW lipopolysaccharide (LPS) i.v. injection, serum glutamic pyruvic transaminases (GPT) activity increased to about eight times that of normal rats. In this model, rats that had been fed a diet containing 1% Hydrangeae Dulcis Folium (HDF) extracts for fifteen days showed significantly lower serum GPT activity (380.0+/-58.2 IU/l) than the control group (3527.0+/-774.1 IU/l). HDF's efficacy was far superior to milk thistle in this model (2950.0+/-915.9 IU/l). When mouse macrophages were treated with HDF extracts at 50 microg/ml, TNF-alpha production induced by LPS was suppressed to about 10% of the control. Rat serum TNF-alpha levels induced by LPS was decreased to 58.7% of the control by administering 1000 mg/kg BW HDF extract p.o. These results indicate that HDF prevents alcohol-induced liver injury through the inhibition of TNF-alpha production.     

Somatic embryogenesis,organogenesis and plant regeneration in taro (<Emphasis Type="Italic">Colocasia esculenta</Emphasis> var. <Emphasis Type="Italic">esculenta</Emphasis>)

Callus was initiated in three different “esculenta” taro cultivars by culturing corm slices in the dark on half-strength MS medium supplemented with 2.0 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) for 20 days followed by subculture of all corm slices to half-strength MS medium containing 1.0 mg/l thidiazuron (TDZ). Depending on the cultivar, 20–30% of corm slices produced compact, yellow, nodular callus on media containing TDZ. Histological studies revealed the presence of typical embryogenic cells which were small, isodiametric with dense cytoplasms. Somatic embryos formed when callus was transferred to hormone-free medium and ~72% of the embryos germinated into plantlets on this medium. Simultaneous formation of roots and shoots during germination, and the presence of shoot and root poles revealed by histology, confirmed that these structures were true somatic embryos. Plants derived from somatic embryos appeared phenotypically normal following 2 months growth in a glasshouse. This method is a significant advance on those previously reported for the esculenta cultivars of taro due to its efficiency and reproducibility.     

Generation of ginsenosides Rg3 and Rh2 from North American ginseng

Rg3 and Rh2 ginsenosides are primarily found in Korean red ginseng root (Panax ginseng C.A. Meyer) and valued for their bioactive properties. We quantified both Rh2 and Rg3 ginseng leaf and Rg3 from root extracts derived from North American ginseng (Panax quinquefolius). Quantification was obtained by application of HPLC with ion fragments detected using ESI-MS. Ginseng leaf contained 11.3+/-0.5 mg/g Rh2 and 7.5+/-0.9 mg/g Rg3 in concentrated extracts compared to 10.6+/-0.4 mg/g Rg3 in ginseng root. No detectable Rh2 was found in root extracts by HPLC, although it was detectable by ESI-MS analysis. Ginsenosides Rg3 and Rh2 were detected following hot water reflux extraction, but not from tissues extracted with 80% aqueous ethanol at room temperature. Therefore ginsenosides Rg3 and Rh2 are not naturally present in North American ginseng, but are products of a thermal process. Using ESI-MS analysis, it was found that formation of Rg3 and Rh2, among other compounds, were a function of heating time and were breakdown products of the more abundant ginsenosides Rb1 and Rc. Our findings that heat processed North American ginseng leaf is an excellent source of Rh2 ginsenoside is an important discovery considering that ginseng leaf material is obtainable throughout the entire plant cycle for recovery of valuable ginsenosides for pharmaceutical use.     

Cytotoxic effects of a decoction of Nigella sativa, Hemidesmus indicus and Smilax glabra on human hepatoma HepG2 cells

A decoction of Nigella sativa seeds, Hemidesmus indicus root and Smilax glabra rhizome is used by traditional medical practitioners in Sri Lanka to treat cancer and has been shown to prevent chemically induced carcinogenesis in rats. The cytotoxicity of the decoction and the individual plant extracts were tested on the human hepatoma HepG2 cell line. The effects of 24 h incubation with different concentrations (0--50 mg/ml) of the extracts on HepG2 cells were determined. Results from MTT and SRB assays, and [(14)C]-leucine and [(3)H]-thymidine uptake demonstrated that the decoction had a strong dose-dependent cytotoxic activity. The greatest inhibitory effects were observed on DNA synthesis with both the decoction (91+/-S.E. 3.7% inhibition) and N. sativa plant extract (88+/-3.8%) even at low concentrations (5 mg/ml). The three individual plant extracts were cytotoxic in the order of potency N. sativa>H. indicus>S. glabra. Flow cytometric analysis using Annexin V and propidium iodide staining showed that after 24 h exposure to the decoction, cells were in the late stage of apoptosis and/or necrosis. Further experiments are worthwhile to determine the anticancer potential of this plant decoction and its components.     

Antioxidant potentials and rosmarinic acid levels of the methanolic extracts of Salvia virgata (Jacq), Salvia staminea (Montbret & Aucher ex Bentham) and Salvia verbenaca (L.) from Turkey

This study was designed to examine the in vitro antioxidant activities and rosmarinic acid levels of the methanol extracts of Salvia virgata, Salvia staminea and Salvia verbenaca. The extracts were screened for their possible antioxidant activity by two complementary test systems, namely DPPH free radical scavenging and beta-carotene/linoleic acid systems. In the first case, the most active plant was S. verbenaca (14.30+/-1.42 microg mg(-1)), followed by S. virgata (65.70+/-2.12 microg mg(-1)). S. staminae exhibited the weakest antioxidant activity in this test system of which IC(50) value is 75.40+/-0.57 microg mg(-1). In beta-carotene/linoleic acid test system, S. verbenaca extract was superior to the other extracts studied (inhibition value is 77.03%+/-0.42). Antioxidant activities of BHT, ascorbic acid, curcumin and alpha-tocopherol were determined in parallel experiments. Activity of rosmarinic acid was also screened for better establishing the relationship between rosmarinic acid level and antioxidant activity for the plant extracts. According to the results obtained by spectrophotometric analysis and further supported by HPLC, S. verbenaca has the highest rosmarinic acid level with a value of 29.30+/-0.24 microg mg(-1). Our results showed that the rosmarinic acid and its derivatives are more likely to be responsible for most of the observed antioxidant activities of Salvia species.     

干燥方式对尾巨桉树皮提取物总三萜含量及其杀螺活性的影响

为探讨干燥方式对尾巨桉树皮提取物总三萜含量的影响和其杀螺作用机理,实验以尾巨桉树皮为研究对象,比较鼓风干燥和冷冻干燥两种干燥方式对其树皮乙醇提取物总三萜含量及杀螺活性的影响。结果表明,当乙醇体积分数为60%时,鼓风干燥和冷冻干燥的尾巨桉树皮乙醇提取物中总三萜含量最高,分别为10.81%和13.90%。两种干燥方式得到的尾巨桉树皮乙醇提取物对福寿螺均有较强的毒杀活性,在50mg/L的浓度下处理72h,福寿螺的死亡率分别到达93.1%和100.00%;同时尾巨桉树皮提取物还能显著抑制福寿螺离水上爬,抑制效果优于同浓度下的对照药剂茶皂素(P<0.05)。与空白对照组相比,经鼓风干燥的尾巨桉树皮提取物处理后,福寿螺头足和肝脏的蛋白质含量变化不大(P>0.05);经过冷冻干燥的尾巨桉树皮提取物处理后,福寿螺头足中蛋白质含量显著降低(P<0.05),而肝脏中蛋白质含量无明显变化(P>0.05)。鼓风干燥和冷冻干燥的尾巨桉树皮提取物均可有效抑制福寿螺头足部中LDH、AKP和AST/GOT的活性(P<0.05)以及肝脏中ALT/GPT和AST/GOT的活性(P<0.05)。冷冻干燥的尾巨桉树皮提取物中三萜含量以及杀螺活性均高于鼓风干燥的树皮提取物。     

Trichomonas vaginalis: identification of a phospholipase A-dependent hemolytic activity in a vesicular subcellular fraction

Trichomonad total extracts (TTE), or vesicular (P30) and soluble (530) subcellular fractions from 3 pathogenic Trichomonas vaginalis strains (GT-3. GT-13. and GT-15), lysed both human and Sprague-Dawley rat erythrocytes in a time- and dose-dependent manner. The entire hemolytic activity of TTE was located in P30, showing 2 peaks of maximum activity, one at pH 6.0 and another at pH 8.0. in the presence of 1 mM Ca2+. Hemolytic activity on rat erythrocytes was greater at pH 6.0 16.71 +/- 0.33 hemolytic units IHU]/mg/hr to 11.60 +/- 0.24 HU/mg/hr) than at pH 8.0 (3.81 +/- 0.30 HU/mg/hr to 5.75 +/- 0.65 HU/mg/hr). and it was greater than that on human red blood cells at pH 6.0 (2.67 +/- 0.19 HU/mg/hr to 4.08 +/- 0.15 HU/mg/hr) or pH 8.0 (2.24 +/- 0.0 9 HU/mg/hr to 2.81 +/- 0.06 HU/mg/hr). The alkaline and acidic hemolytic activity diminished (60-93% at pH 6.0 and 78-93% at pH 8.0) by the effect of 80 microM Rosenthal's inhibitor, which also inhibited 27-45% and 29-54% trichomonad alkaline and acidic phospholipase A activities, respectively. Vesicles, vacuoles, and hydrogenosomes were rich in P30. Trichomonas vaginalis has a hemolytic PLA, which could be involved in its cytopathogenic mechanism.     

Angiostrongylus cantonensis: experimental study on the susceptibility of apple snails, Pomacea canaliculata compared to Pila polita

Six groups (15 snails/group) of Pomacea canaliculata and Pila polita were infected orally with 0 (control), 200, 400, 800, 1600 and 3200 first-stage Angiostrongylus cantonensis larvae (L1). The respective mean+/-SD third stage larvae (L3) worm recovery 1-month post-infection (p.i.) for P. canaliculata was 0, 1.4+/-5.42 (0.7%), 0.13+/-0.35 (0.03%), 0.07+/-0.26 (0.009%), 0.07+/-0.26 (0.004%), 0, and for P. polita 0, 64.33+/-21.38 (32.25%), 115.36+/-36.82 (28.93%), 265.33+/-90.01 (33.27%), 471.33+/-92.98 (29.60%) and 849.00+/-243.23 (26.61%). The susceptibility of A. cantonensis in P. polita was dose-dependent (p<0.001). In the three groups (nine snails/group) of P. polita given 500 L1, we studied the distribution of L3 in the internal organs (i.e., foot, head+esophagus, kidney, albumin gland, mantle, intestine, digestive gland) and found the highest density after 1, 2 and 3 months p.i. in the mantle at 29.37%, 31.09% and 37.45%. The infection rate in P. canaliculata was too low to study distribution rates.     

Fatty acid and carotenoid production by Sporobolomyces ruberrimus when using technical glycerol and ammonium sulfate

The production of carotenoids, lipid content, and fatty acid composition were all studied in a strain of Sporobolomyces ruberrimus when using different concentrations of technical glycerol as the carbon source and ammonium sulfate as the nitrogen source. The total lipids represented an average of 13% of the dry weight, and the maximum lipids were obtained when using 65.5 g/l technical glycerol (133.63 mg/ g). The optimal conditions for fatty acid production were at 27 degrees C using 20 g of ammonium sulfate and a pH range from 6 to 7, which produced a fatty acid yield of 32.5+/-1 mg/g, including 1.27+/- 0.15 mg of linolenic acid (LNA), 7.50+/-0.45 mg of linoleic acid (LLA), 5.50+/-0.35 mg of palmitic acid (PA), 0.60+/-0.03 mg of palmitoleic acid (PAL), 1.28+/-0.11 mg of stearic acid (SA), 9.09+/-0.22 mg of oleic acid, 2.50+/-0.10 mg of erucic acid (EA), and 4.25+/-0.20 mg of lignoceric acid (LCA), where the palmitic, oleic, and linoleic acids combined formed about 37% of the total fatty acids. The concentration of total carotenoids was 2.80 mg/g when using 20 g of ammonium sulfate, and consisted of torularhodin (2.70 mg/g) and beta-carotene (0.10 mg/ g), at 23 degrees C and pH 6. However, the highest amount with the maximum specific growth rate was obtained (micromax=0.096 h(-1)) with an ammonium sulfate concentration of 30 g/l.     

Melanogenesis inhibitory effects of methanolic extracts of Umbilicaria esculenta and Usnea longissima

The primary objective of this study was to assess the in vitro melanogenesis inhibitory effects of methanolic extracts of the edible and medicinal lichens, Umbilicaria (Gyrophora) esculenta and Usnea longissima. The quantities of the total phenolic compounds of methanolic extract of the two lichen extracts were determined to be 1.46% and 2.62%, respectively. In order to evaluate the antioxidative effects of the extracts, we also measured electron donating abilities (EDA) and lipid peroxidation rates. The EDA values measured by the reduction of 1.1'-diphenyl-2-picrylhydrazyl (DPPH) were 72.8% and 80.7% for the extracts, with SC50 (median scavenging concentration) values of 1.29+/-0.05 mg/ml and 1.03+/-0.06 mg/ml, respectively. The rates of inhibition of lipid peroxidation using linoleic acid were 92.1% and 97.3% for the extracts, with IC50 (median inhibitory concentration) values of 0.57+/-0.05 mg/ml and 0.53+/-0.06 mg/ml, respectively. The inhibitory rates of the extracts against tyrosinase were 67.4% and 84.8%, respectively. The extracts were shown to reduce melanin formation in human melanoma cells. Melanin contents in the samples treated with 0.01% and 0.1% U. esculenta were 47.1% and 31.2%, respectively, and those treated with 0.01% and 0.1% Usnea longissima were 51.1% and 34.9%, respectively, whereas a value of 54.0% was registered when ascorbic acid was utilized as a positive control. In addition to direct tyrosinase inhibition, it was determined that the lichen extracts affected the activity of tyrosinase via the inhibition of tyrosinase glycosylation. As a result, the methanolic extracts of U. esculenta and Usnea longissima evidenced melanogenesis inhibitory effects, which occurred via multiple routes.     

In vitro keratinocyte antiproliferant effect of Centella asiatica extract and triterpenoid saponins.

Psoriasis is a hyperproliferative skin disorder estimated to be present in 1-3% of most populations. Conventional therapy using corticosteroids, Vitamin D analogs and cytotoxic agents eg psoralens is associated with low success rate and many side effects. Traditional plant remedies may provide leads for new treatments. A rapid-throughput, in vitro bioassay has been utilised to examine plants for inhibitory effects on the growth of SVK-14 keratinocytes. Centella asiatica, a reputed anti-psoriatic herb, has been compared against the psoralen-containing seeds of Psoralea corylifolia and the synthetic anti-psoriatic agent dithranol (anthralin). Aqueous extracts of Psoralea corylifolia and Centella asiatica inhibited keratinocyte replication with IC50 values of 18.4 +/- 0.6 microg/ml and 209.9 +/- 9.8 mg/ml respectively prior to treatment with polyvinylpolypyrrolidone (PVPP) and 36.3 +/- 3.3 mg/ml and 238.0 +/- 2.5 mg/ml respectively after PVPP treatment of the extracts. The effect produced by C. asiatica is thus unlikely to be due to phenolic compounds. It may, however, be due to its two constituent triterpenoid glycosides madecassoside and asiaticoside which had IC50 values of 8.6 +/- 0.6 microM respectively. These values were comparable to their concentrations in the crude extract and to the IC50 of dithranol (5.1 +/- 0.4 microM). These results suggest that the potential use of C. asiatica extracts as a topical anti-psoriatic agent is worthy of further investigation.     

Iron and nitrosative metabolism in the Antarctic mollusc Laternula elliptica

The objective of this work was to study Fe distribution, and oxidative and nitrosative metabolism in Laternula elliptica for physiological analysis and interspecific comparisons. Lipid peroxidation, superoxide dismutase and catalase activity and total Fe content were estimated in the digestive glands (DG) of L. elliptica. The labile Fe pool (LIP) represents the amount of cellular Fe responsible for catalyzing radical-dependent reactions. LIP assessed by the calcein assay, represents 3.5% of the total Fe in L. elliptica. Experimental isolation of ferritin (Ft) was performed. Subunit analyses of the protein by SDS-polyacrilamide gel electrophoresis indicated that the protein was composed of 20.6kDa protein subunits, consistent with the horse spleen Ft and the molecular weight markers, however, a higher molecular mass subunit could appear. The identity of the protein was confirmed by Western blot analysis. The nitrate+nitrite content was 73±7pmol/mg fresh mass (FW). The nitric oxide (NO) content in DG homogenates, assessed by electronic paramagnetic resonance (EPR) spin trapping measurements using the NO trap sodium-N-methyl-D-glucamine dithiocarbamate-Fe at room temperature, was 30±2pmol/mg FW. Nitric oxide synthase-like activity (1.50±0.09pmol/mg FW min) was assessed by measuring NO production by EPR in the presence of L-arginine (L-A) and NADPH. This activity was significantly inhibited by L-A analogs such as Nω-nitro-L-arginine methyl ester hydrochloride (-77%) and Nω-nitro-L-arginine (-62%), or by the lack of added L-A (-55%). The data presented here documented the physiological presence of labile Fe, Ft and highly reactive nitrogen species, and are the first evidence that support the hypothesis that NO being generated in L. elliptica might contribute to restrict oxidative damage by a close link with Fe metabolism.     

In vitro propagation and rhizome formation in Curcuma longa Linn

Turmeric (Curcuma longa Linn.) which is cultivated by underground rhizomes is a slow propagating species. Multiplication and callus induction starting from the rhizome buds and shoot tips of C. longa in MS medium was carried out. A combination of naphthalene acetic acid (NAA; 1.0 mg/l) with kinetin (Kn; 1.0 mg/l) or NAA (1.0 mg/l) with 6-benzylaminopurine (BAP; 2.0 mg/l) was optimum for rapid clonal propagation of turmeric. A concentration of 2.5-3.0 mg/l of 2,4-dichlorophenoxy-acetic acid (2,4-D) was found to be optimum for callus induction. Regeneration of plantlets from a callus was successfully conducted in MS medium supplemented with standard growth hormones for multiplication at 25 +/- 2 degrees C under a 16 h photoperiod. These plantlets were successfully transferred to the field. Plantlets (4-month-old) were incubated in a medium containing different concentrations of sucrose supplemented with NAA (0.1 mg/l) and Kn (1.0 mg/l) at 27 +/- 2 degrees C under an 8 h photoperiod for induction of rhizomes. In vitro rhizome formation was observed in media containing 6 and 8% sucrose.     

In vitro evaluation of antibacterial, antioxidant, cytotoxic and apoptotic activities of the tubers infusion and extracts of Cyperus rotundus

The in vitro antibacterial, antioxidant, cytotoxic and apoptotic activities from tubers extracts of Cyperus rotundus (Cyperaceae) were investigated. Antibacterial activity of different extracts was evaluated against five bacterial reference strains. A marked inhibitory effect was observed against Salmonella enteritidis, Staphylococcus aureus and Enterococcus faecalis with total oligomers flavonoids (TOFs) and ethyl acetate extracts. In addition to their antibacterial activity, the same extracts showed a significant ability to inhibit nitroblue tetrazolium reduction by the superoxide radical in a non-enzymatic superoxide generating system. Apoptosis, a highly organized physiological mechanism to eliminate injured or abnormal cells, is also implicated in multistage carcinogenesis. It was observed that TOF and ethyl acetate extracts suppressed growth and proliferation of L1210 cells derived from murine lymphoblastic leukaemia. Morphological features of treated cells and characteristic DNA fragmentation revealed that the cytotoxicity was due to induction of apoptosis. This study confirms that TOF and ethyl acetate extracts of C.rotundus possess antibacterial and antioxidant properties and provoke DNA fragmentation, a sign of induction of apoptosis. These results were correlated with chemical composition of the tested extracts.     

Citrinolactones A, B and C, and Sclerotinin C, plant growth regulators from Penicillium citrinum

New plant growth regulators, named citrinolactones A (1), B (2) and C (3) and sclerotinin C (4), were isolated from Penicillium citrinum and their structures established by spectroscopic methods including 2D NMR. Compounds 1 and 4 increased root growth in proportion to their concentration from 3 to 300 mg/l. In contrast, 2 completely inhibited root growth at a concentration of 300 mg/l and 3 did not show any effect on root growth in a concentration range of 3-300 mg/l.     

Changes in plasma angiotensin-converting enzyme activity and noradrenaline responses to long-term nitric oxide inhibition vary depending on their basal values in chickens

In this study, we investigated the effects of N(omega)-nitro-L-arginine (L-NNA) on arterial blood pressure (BP), plasma noradrenaline (NA) and adrenaline (A) levels and angiotensin-converting enzyme (ACE) activity. L-NNA was applied with tap water (1 mg/ml) from the 3rd to the 8th week of age (group L-NNA1). In Experiment 1, long-term L-NNA application increased BP compared to the control group (group C1) (L-NNA1 = 131.4 +/- 6.3, n = 6; C1 = 82.7 +/- 4.7 mm Hg, n = 7) but decreased plasma noradrenaline and adrenaline levels and ACE activity (NA levels: C1 = 15.5 +/- 0.8, n = 7; L-NNA1 = 8.6 +/- 0.5 ng/ml, n = 7; A levels: C1 = 15.5 +/- 0.8, n = 7; L-NNA1 = 6.0 +/- 0.5 ng/ml, n = 7; ACE activities: C1 = 87.3 +/- 3.1, n = 6; L-NNA1 = 46.2 +/- 1.9 U/l, n = 5). On the other hand, in Experiment 2 (carried out under the same conditions and in age-matched chickens), blood pressure, plasma noradrenaline levels and ACE activity were found to differ in the control group (C2) (BP = 141.4 +/- 15.5 mm Hg, n = 7; NA = 1.1 +/- 0.4 ng/ml, n = 7; ACE = 57.2 +/- 5.3 U/l, n = 7) as compared to C1, while plasma adrenaline levels were similar. In this series, long-term L-NNA application (group L-NNA2) did not change the BP, but surprisingly increased noradrenaline and ACE values (values of L-NNA2: BP = 165.7 +/- 15.6 mm Hg, n = 7; NA = 9.3 +/- 1.3 ng/ml, n = 8; ACE = 149.4 +/- 16 U/l, n = 8) while decreasing plasma adrenaline levels. L-arginine addition to L-NNA treatment completely reversed plasma noradrenaline and ACE activity values. These results indicate the modulatory activity of an L-arginine-NO pathway on adrenaline release as well as on the renin-angiotensin system in chickens.     

Water extract of the root of Lindera strychnifolia slows down the progression of diabetic nephropathy in db/db mice

We examined a possible preventive effect of Linderae radix (LR), the root of Lindera strychnifolia, on the progression of diabetic nephropathy. Water extract of Linderae radix (LR extract) was orally administered to the C57BL/KsJ-db/db (db/db) mice, a model of genetic diabetes, at a dose of 730 mg/kg/day for 12 week. The LR extract treatment did not affect glucose metabolism and systolic pressure. However, it resulted in a better renal function as evaluated by creatinine clearance (Ccr) and serum creatinine than the control; Ccr and serum creatinine were progressively worsened in controls (0.13+/-0.01 (l/day) and 0.69+/-0.04 (mg/dl), respectively) whereas unchanged in the treated group (0.24+/-0.03 (l/day), p<0.05 and 0.53+/-0.04 (mg/dl), p<0.05, respectively). Kidneys of the LR extract-treated group showed glomeruli with greater area and cell population, smaller glomerular sclerotic index, and less fibrosis in glomeruli, where apoptotic rate of glomerular cells were decreased compared with the control kidneys. Furthermore, renal TGF-beta(1) expression was decreased in the LR extract-treated group. These findings suggest that the LR therapy can be a novel therapeutic approach against diabetic nephropathy.