ABSTRACT
Plants use nitrate and ammonium as major nitrogen (N) sources, each affecting root development through different mechanisms. However, the exact signaling pathways involved in root development are poorly understood. Here, we show that, in Arabidopsis thaliana, either disruption of the cell wall-localized ferroxidase LPR2 or a decrease in iron supplementation efficiently alleviates the growth inhibition of primary roots in response to NH4+ as the N source. Further study revealed that, compared with nitrate, ammonium led to excess iron accumulation in the apoplast of phloem in an LPR2-dependent manner. Such an aberrant iron accumulation subsequently causes massive callose deposition in the phloem from a resulting burst of reactive oxygen species, which impairs the function of the phloem. Therefore, ammonium attenuates primary root development by insufficiently allocating sucrose to the growth zone. Our results link phloem iron to root morphology in response to environmental cues.
Subject(s)
Ammonium Compounds/metabolism , Arabidopsis/metabolism , Iron/metabolism , Nitrogen/metabolism , Phloem/metabolism , Plant Roots/metabolism , Arabidopsis/genetics , Arabidopsis/growth & development , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Cell Wall/genetics , Cell Wall/metabolism , Ceruloplasmin/genetics , Ceruloplasmin/metabolism , Gene Expression Regulation, Developmental , Gene Expression Regulation, Plant , Glucans/metabolism , Mutation , Nitrates/metabolism , Plant Roots/genetics , Plant Roots/growth & development , Plants, Genetically Modified , Reactive Oxygen Species/metabolism , Seedlings/genetics , Seedlings/growth & development , Seedlings/metabolismABSTRACT
BACKGROUND AND AIM: Disordered hepatic energy metabolism is found in obese rats with insulin resistance (IR). There are insufficient experimental studies of electroacupuncture (EA) for IR and type 2 diabetes mellitus (T2DM). The aim of this study was to probe the effect of EA on disordered hepatic energy metabolism and the adenosine monophosphate (AMP)-activated protein kinase (AMPK)/mammalian target of rapamycin complex 1 (mTORC1)/ribosomal protein S6 kinase, 70-kDa (p70S6K) signaling pathway. METHODS: Zucker Diabetic Fatty (ZDF) rats were randomly divided into three groups: EA group receiving EA treatment; Pi group receiving pioglitazone gavage; and ZF group remaining untreated (n = 8 per group). Inbred non-insulin-resistant Zucker lean rats formed an (untreated) healthy control group (ZL, n = 8). Fasting plasma glucose (FPG), fasting insulin (FINS), C-peptide, C-reactive protein (CRP) and homeostatic model assessment of insulin resistance (HOMA-IR) indices were measured. Hematoxylin-eosin (H&E) staining was used to investigate the liver morphologically. The mitochondrial structure of hepatocytes was observed by transmission electron microscopy (TEM). Western blotting was adopted to determine protein expression of insulin receptor substrate 1 (IRS-1), mTOR, mTORC1, AMPK, tuberous sclerosis 2 (TSC2) and p70S6K, and their phosphorylation. RT-PCR was used to quantify IRS-1, mTOR, mTORC1, AMPK and p70S6K mRNA levels. RESULTS: Compared with the ZF group, FPG, FINS, C-peptide, CRP and HOMA-IR levels were significantly reduced in the EA group (p < 0.05, p < 0.01). Evaluation of histopathology showed improvement in liver appearances following EA. Phosphorylation levels of AMPK, mTOR and TSC2 decreased, and IRS-1 and p70S6K increased, in hepatocytes of the ZF group, while these negative effects appeared to be alleviated by EA. CONCLUSIONS: EA can effectively ameliorate IR and regulate energy metabolism in the ZDF rat model. AMPK/mTORC1/p70S6K and related molecules may represent a potential mechanism of action underlying these effects.
Subject(s)
Diabetes Mellitus, Type 2 , Electroacupuncture , Insulin Resistance , AMP-Activated Protein Kinases/metabolism , Animals , C-Peptide/metabolism , C-Peptide/pharmacology , Diabetes Mellitus, Type 2/therapy , Energy Metabolism , Insulin/metabolism , Mammals/metabolism , Mechanistic Target of Rapamycin Complex 1/metabolism , Rats , Rats, Zucker , Ribosomal Protein S6 Kinases, 70-kDa/genetics , Ribosomal Protein S6 Kinases, 70-kDa/metabolism , Ribosomal Protein S6 Kinases, 70-kDa/pharmacology , Signal Transduction , TOR Serine-Threonine Kinases/genetics , TOR Serine-Threonine Kinases/metabolism , TOR Serine-Threonine Kinases/pharmacologyABSTRACT
The interaction of endophytes and host plant is an effective mean to regulate the growth and secondary metabolism of medicinal plants. Here we want to elucidate the effects and mechanism of Phoma herbarum D603 on the root development and tanshinone synthesis in root of Salvia miltiorrhiza by endophyte-plant coculture system. The mycelium of P. herbarum D603 was colonized in the root tissue space, and formed a stable symbiotic relationship with host plant. The in vitro activities analysis showed that the concentration of IAA produced by D603 can reach(6.45±0.23) µg·mL~(-1), and this strain had some abilities of phosphorus solubilization and siderophore production activities. The coculture experiment showed that strain D603 can significantly promote the synthesis and accumulation of tanshinones in the root of S. miltiorrhiza, in which after 8 weeks of treatment with D603, the content of tanshinone â ¡_A in the roots reached up to(1.42±0.59) mg·g~(-1). By the qRT-PCR analysis results, we found that D603 could improve the expression levels of some key genes(DXR, DXS, GGPP, HMGR, CPS) of tanshinone biosynthesis pathway in host plant S. miltiorrhiza, but the promoting effect mainly occurred in the early stage of the interaction, and the enzyme activity level decreased in varying degrees of the later stage. In summary, seed-associated endophyte P. herbarum D603 can promote the growth and root development of S. miltiorrhiza by producing hormones, promoting nutrient absorption and siderophore production, and promote the synthesis and accumulation of tanshinones by regulating the expression level of key genes in the synthetic pathway in S. miltiorrhiza.
Subject(s)
Abietanes/biosynthesis , Ascomycota/growth & development , Plant Roots/microbiology , Salvia miltiorrhiza/microbiology , Endophytes/growth & development , Plant Roots/metabolism , Salvia miltiorrhiza/metabolism , Seeds/microbiologyABSTRACT
OBJECTIVE: Gut microbiota plays a key role in metabolism and health in diabetes patients with gastrointestinal microbiota dysbiosis. Thus, regulating the ecological balance of gut microbiota may provide a pathway toward improvement for these patients. Our previous study showed that functional ingredients in tea may inhibit cornstarch digestion in vitro. METHODS: A cornstarch-tea diet was developed, and in this study we investigated the effects of such a diet on blood glucose and gut microbiota in diabetic mice. RESULTS: Diabetes resulted in significant weight loss, hyperphagia and hyperglycemia. 16S rDNA sequencing revealed that in diabetes there is significantly increased Bacteroidaceae, Helicobacteraceae, Ruminococcaceae, Enterobacteriaceae, Rikenellaceae and Saccharibacteria_genera_incertae_sedis, and significantly decreased Lactobacillaceae, Prevotellaceae, Coriobacteriaceae, Verrucomicrobiaceae and Bifidobacteriaceae. The cornstarchâtea diet resulted in a trend toward reduced blood glucose, with particularly increased levels of Coriobacteriaceae, Lactobacillaceae, Prevotellaceae and Bifidobacteriaceae, and decreased Bacteroidaceae, Ruminococcaceae, Helicobacteraceae and Enterobacteriaceae. CONCLUSIONS: Instant tea and matcha supplementation had beneficial effects on regulation of blood glucose and gut microbiota, reversing the changes in microbiota caused by alloxan injection. The cornstarchâtea regulation pathway is involved in bacterium group regulation rather than single-species regulation, which suggests that cornstarch combined with tea may be used as a functional food supplement for diabetes patients.
Subject(s)
Diabetes Mellitus, Experimental/microbiology , Diabetes Mellitus, Type 2/microbiology , Dietary Supplements , Dysbiosis/drug therapy , Gastrointestinal Microbiome/drug effects , Plant Extracts/pharmacology , Tea/chemistry , Animals , Bacteria/isolation & purification , Diabetes Mellitus, Experimental/drug therapy , Diabetes Mellitus, Type 2/drug therapy , Dysbiosis/microbiology , Female , Mice , Weight Loss/drug effectsABSTRACT
In this study, the improving effects of green tea powder, soluble tea, and tea polyphenols on the mixing and tensile qualities of dough and texture of tea-enriched noodles, as well as the physico-chemical and structural properties of gluten proteins were progressively investigated. Dough strength and noodle texture were significantly increased by all the three tea products. Tea polyphenols in particular presented the most effective improvement with highest dough stability, resistance, and noodle chewiness. SEM indicated that tea products all induced a more developed gluten network, and polyphenol noodle showed the most continuous and ordered structure. FT-IR and fluorescence spectrum indicated that tea polyphenols promoted an enhancement in α-helix structure and the hydrophobic interactions. Tea polyphenols induced the SH/SS interchange during processing and cooking, and enhanced the water-solids interaction in noodles. AFM results showed that polyphenols induced the polymerization of gluten protein molecular chains, with increased chain height and width.
Subject(s)
Polyphenols/chemistry , Tea/chemistry , Triticum/chemistry , Chemical Phenomena , Cooking , Glutens/chemistry , Spectroscopy, Fourier Transform InfraredABSTRACT
OBJECTIVE: To compare the differences in clinical effects on hyperlipidemia of turbid phlegm obstruction pattern/syndrome treated with the different Jin's three-needle therapies so as to provide a new approach and theoretic evidence for the clinical optimal scheme of acupuncture on hyperlipidemia. METHODS: A total of 90 patients were randomly divided into education group, electroacupuncture group and catgut embedding group (30 cases in each). The routine health education was given to the education group. On the base of the treatment as the education group, electroacupuncture was applied to the electroacupuncture group for 30 min each time, twice a week; and the catgut embedding was applied to the catgut embedding group at the same acupoints as the electroacupuncture group, once a week. The treatment was given consecutively for 8 weeks in each group. Before and after treatment, the obesity indices [weight, waistline, body mass index (BMI)], blood lipid indices[serum total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C)] and insulin resistance indices [fasting blood glucose(FBG), fasting plasma insulin(FINS), homeostasis model assessment-estimated insulin resistance (HOMA-IR)] were observed in the three groups before and after treatment. RESULTS: After treatment, in the electroacupuncture group and the catgut embedding group, the results of the obesity indices, e.g. weight, waistline and BMI, the levels of blood lipid, e.g.TC, TG, LDL-C and the insulin resistance indices, e.g. FINS and HOMA-IR were all obviously decreased compared with those before treatment (P<0.05, P<0.01), and the level of HDL-C apparently increased than that before treatment (P<0.01). In the catgut embedding group, FBG was obviously decreased after treatment as compared with that before treatment (P<0.01). After treatment, the improvements in LDL-C and HDL-C in the catgut embedding group were superior to those in the electroacupuncture group (P<0.05). Regarding the obesity indices and insulin resistance indices, the differences were not statistically significant in comparison between the catgut embedding group and the electroacupuncture group (all P>0.05). The total effective rate was 90.0% in the catgut embedding group (27/30) and it was 83.3% (25/30) in the electroacupuncture group, either of them was better than 60.0% (18/30) in the education group , indicating the statistical significance (P<0.01, P<0.05). CONCLUSION: On the base of health education, either the catgut embedding therapy or electroacupuncture of Jin's three-needle treatment achieves the positive regulation on the abnormal lipid metabolism and insulin resistance. The hypoglycemic effect and the impro-ving effect in LDL-C and HDL-C of the catgut embedding therapy are superior to electroacupuncture.
Subject(s)
Electroacupuncture , Hyperlipidemias , Acupuncture Points , Catgut , Humans , Hyperlipidemias/therapyABSTRACT
Insulin resistance (IR) is a common pathophysiological basis of many chronic diseases, such as obesity, type 2 diabetes mellitus (T2DM), nonalcoholic fatty liver disease, cerebral vascular disease, cardiovascular and neurodegenerative diseases, etc. Acupuncture therapy has been demonstrated to have a positive role in reducing IR level in clinical practice. In the present paper, we summarized development of researches on the mechanism of acupuncture therapy underlying improvement of IR in recent 10 years from 1) regulating expression of hypothalamic phosphatidylinositol-3-kinase (PI3K)-p85 and PI3K-P110 proteins in obesity rats; 2) regulating the levels of some related proteins of insulin target tissues (liver and skeletal muscle), such as insulin receptor substrate-1 (IRS)-1 and -2, glucose transporter mRNAs and proteins, sterol regulatory element-binding protein 1 (SREBP-1) and fatty acid synthetase proteins; 3) suppressing inflammatory reaction of liver tissue and down-regulating serum adiponectin in T2DM rats; 4) raising the activity of superoxide dismutase (SOD) and reducing the levels of reactive oxygen species, and malondialdehyde (MDA) contents of quadriceps femoris in spontaneous IR rats; and 5) attenuating structural injury of pancreas islet and apoptosis of pancreatic ß cells in diabetes rats. Multi-levels and various systems of the neuro-endocrine-immune networks are involved in the actions of acupuncture in the improvement of IR. In the future, more attention should be paid to the study on the acupoint specificity, suitable acupoint combinations and stimulus parameters in clinical treatment of IR related various metabolic diseases, further optimizing clinical treatment protocols.
Subject(s)
Acupuncture Therapy , Insulin Resistance , Animals , Diabetes Mellitus, Type 2 , Insulin , Insulin Receptor Substrate Proteins , RatsABSTRACT
OBJECTIVE: To observe the effect of eletroacupuncture (EA) intervention on lipid metabolism and expression of AMP-activated kinase (AMPK), p38 mitogen-activated protein kinase (p38 MAPK) and peroxisome proliferator-activated receptor γ (PPARγ) protein in the liver in rats with insulin resistance (IR), so as to reveal its mechanisms underlying improvement of IR. METHODS: Forty male SD rats were randomly divided into blank control, model, medication, and EA groups (nï¼8 in each). The IR model was established by feeding the rats with high-fat diet for 12 weeks. After successful establishment of model, the rats in the blank control group and model group were fixed in the self-made rat bag without receiving any treatment. The rats in the medication group were treated by gavage of pioglitazone (10 mL/kg). EA (2 Hz /100 Hz, 1 mA) was applied to bilateral "Fenglong"(ST40) and "Sanyinjiao"(SP6) for 20 min, once a day, for continuous 14 days for rats in the EA group. The ultrastructure of the liver tissue was observed by transmission electron microscope (TEM). Blood samples were taken from the abdominal aorta for detecting serum C-peptide (C-P), adiponectin (ADP), leptin (LEP) and resistin (RES) contents using enzyme linked immunosorbent assay (ELISA). The expression levels of AMPK, p38 MAPK and PPARγ proteins in the liver tissue were detected by Western blot. RESULTS: After modeling, the contents of serum C-P, LEP and RES, and the expression of liver p38 MAPK protein were significantly up-regulated (P<0.01, P<0.05), and the content of ADP and expression of AMPK and PPARγ significantly down-regulated in the model group compared with the blank control group (P<0.01). The increased contents of C-P, LEP and RES, and p38 MAPK protein expression and the decreased serum ADP and hepatic AMPK and PPARγ expression levels were completely reversed in both the EA and medication groups relevant to the model group (P<0.01, P<0.05). No significant differences were found between the EA and medication groups in up-regulating the levels of ADP, AMPK and PPARγ and in down-regulating the levels of C-P, LEP, RES and p38 MAPK(P>0.05). Outcomes of TEM showed that morphological structure of liver mitochondria was damaged, including a large number of lipid droplets, being blur in appearance, rupture of partial membrane, dissapearance of partial mitochondrial crests with vacuolus-like appearance and decrease of rough endoplasmic reticulum in the model group, which was relatively milder in both EA and medication groups. CONCLUSION: EA intervention is able to improve the disorder of lipid metabolism of IR rats, which may be associated with its effects in lowering the activity of fatty acid synthesis-related enzymes and regulating AMPK/p38 MAPK/PPARγ signaling to improve IR in the liver tissue.
Subject(s)
Electroacupuncture , Insulin Resistance , Acupuncture Points , Animals , Diet, High-Fat , Lipids , Liver , MAP Kinase Signaling System , Male , Rats , Rats, Sprague-Dawley , p38 Mitogen-Activated Protein KinasesABSTRACT
OBJECTIVE: To observe the effect of electroacupuncture(EA) of "Fenglong" (ST 40) and "Sanyinjiao" (SP 6) on lipid metabolic disorder, insulin resistance (IR) and expression of sterol regulatory element blinding protein-1 (SREBP-1) c and fatty acid synthase (FAS) proteins in the liver tissue in hyperlipidemia rats with IR, so as to reveal its mechanisms underlying improvement of IR. METHODS: Forty male SD rats were randomly divided into blank control, model, medication and EA groups (nï¼8 in each group). The IR model was established by feeding the rat with high-fat diet. Rats of the medication group were treated by intragastric administration of pioglitazone (10 mL/kg). For rats of the EA group, EA (2 Hz/100 Hzï¼1 mA) was applied to bilateral ST 40 and SP 6, once daily for 14 days. The insulin sensitivity index (ISI) was assessed by calculating 60ï¼120 min glucose infusion rate (GIR 60ï¼120) with euglycemic hyperinsulinemic clamp in reference to Kraegen's and colleagues' methods. Fasting blood samples (10 mL) were collected and analyzed for fasting blood glucose (FBG) using enzyme method, serum fasting insulin(FINS) using ELISA, free fatty acid(FFA) using spectrophotometry, and total triglyceride(TG) and total cholesterol(TC) employing glycerine phosphate oxidase peroxidase (GPO-PAP) assay, low density lipoprotein(LDL), high density lipoprotein(HDL) levels using combined filiter paper activity and lipase activity methods, respectively. The IR level was assessed by calculating homeostatic model assessment of insulin resistance (HOMA-IR) using the formula (FBG×FINS)/22.5. The expression levels of SREBP-1 c and FAS proteins in the liver tissue were detected by Western blot. RESULTS: Following modeling, the GIR 60ï¼120 and serum HDL were significantly decreased(P<0.01), and the HOMA-IR, serum FBG, FINS, FFA, TG, TC and LDL, and the expression levels of hepatic SREBP-1 c and FAS proteins were significantly increased in comparison with the blank control group(P<0.01). After the intervention, the decreased GIR 60ï¼120 and serum HDL levels were considerably up-regulated (P<0.01), and the increased FBG, FINS, FFA, TG, TC and LDL, and hepatic SREBP-1 c and FAS protein levels were notably down-regulated in both EA and medication groups relevant to the model group (P<0.05, P<0.01). No significant differences were found between the EA and medication groups in all the indexes mentioned above (P>0.05). CONCLUSION: EA intervention is able to improve the disorder of lipid metabolism of IR rats, which may be associated with its effects in reducing the expression of SREBP-1 c and FAS proteins and in lowering the synthesis of fatty acid.
Subject(s)
Hyperlipidemias , Insulin Resistance , Metabolic Diseases , Animals , Electroacupuncture , Fatty Acid Synthases , Hyperlipidemias/therapy , Liver , Male , Protein C , Rats , Rats, Sprague-Dawley , Sterol Regulatory Element Binding Protein 1 , SterolsABSTRACT
OBJECTIVE: To analyze the characteristics and rules of acupoint selection for acupuncture treatment of insulin resistance. METHODS: Data collections were conducted by searching references on acupuncture treatment of insulin resistance in PubMed, CNKI, VIP data base from 1991 to 2016, and acupuncture prescription data base for acupuncture treatment of insulin resistance was established. Data mining was applied to analyze the characteristics and rules of acupoint selection. RESULTS: A total of 64 papers were recruited, and 73 acupoints were selected in these papers. It was found that the acupoints as Zusanli (ST 36), Sanyinjiao (SP 6), Fenglong (ST 40) and Taichong (LR 3) were used with highest frequencies. All acupoints selected distributed in 13 meridians, especially Foot Yangming Stomach Meridian, Foot Taiyin Bladder Meridian, and Conception Vessel with a total frequency of 58.07%. The special acupoints including five-shu points, eight confluent points and back-shu points, accounted for 56.71%. CONCLUSIONS: This study excavated the regular acupoint selection and acupoints compatibility for acupuncture treatment in patients with insulin resistance, giving evidence based confirming and direction for acupuncture clinical treatment.
Subject(s)
Acupuncture Points , Acupuncture Therapy , Data Mining , Databases, Factual , Humans , Insulin Resistance , PubMed/statistics & numerical dataABSTRACT
In this study, polyacrylicacid precipitation alkalescence protein from Momordica charantia L. seeds was studied, and the effect of conditions on experiment was also evaluated. Isoelectric precipitation is achieved by adjusting the pH of a protein solution and is based on that a protein's solubility is at minimum at its pI. The sample was titrated to pH 6.0 with citric acid, and 14.62% proteins were precipitated. With hydrochloric acid to pH 4.0, 32.49% proteins were precipitated. With the acetic acid to pH 6.0 and pH 4.0, 26.17% and 38.72% proteins were precipitated, respectively. In the 1 mL Bitter melon seeds extraction(pH 4.0) adjusted by acetic acid, hydrochloric acid and citric acid, the optimum dosage of PAA (1%) precipiting alkalescency protein (pl 8.65-9.30) was 100 microL, 120 microL and 100 microL, respectively. The respective extraction (1mL) was titrated to pH 5.0, pH 4.0, and pH 3.0 by acetic acid. After isoelectric precipitation, the PAA precipitation protein was performed. When concentration of PAA (1%) was 160 microL/mL, the protein decreased in the supernatant was 33.77% at pH 5.0, and 43.56% at pH 3.0. When concentration of PAA (1%) was 120 microL/mL, the protein decreased in the supernatant was 30.83% at pH 4.0. PAA-Protein complex could redissolve in alkaline conditions (pH > 9.0) and the protein most easilly redissolved when the NaCL was 3.0%. The bitter melon seeds extraction after PAA purification flowed through the Sephadex G-75 columns. The peaks I and II were obtained after 175 min and 300 min, respectively. SDS-PAGE and IEF analysis showed that the molecule weight from peaks I was 30 kD with pI 9.5, peaks II 10 kD with pI 9.3.