L-valine is an important essential branched-chain amino acid widely used in industries such as feed, pharmaceuticals, and food. In order to further enhance the production performance of L-valine, this study systematically engineered the metabolism of a Corynebacterium glutamicum strain, preserved in the laboratory, which is capable of producing L-valine. First, strain VH-9 was obtained by enhancing the precursor supply, synthesis pathway, and transport system of L-valine. In a 5 L fermenter, the titer, yield, and productivity of L-valine were 76.6 g/L, 0.45 g/g, and 2.39 g/(L·h), respectively. Furthermore, strain VH-18 was obtained by enhancing the uptake of substrate glucose and balancing energy supply to reduce succinate accumulation, with the titer, yield, and productivity of L-valine increased to 82.7 g/L, 0.52 g/g, and 2.58 g/(L·h), respectively. After optimization of fermentation conditions, the titer, yield, and productivity of L-valine in strain VH-18 were further improved to 88.7 g/L, 0.54 g/g, and 2.77 g/(L·h), respectively. This study has achieved the high-efficiency production of L-valine through a systems metabolic engineering strategy.
Corynebacterium glutamicum/genetics* ; Metabolic Engineering/methods* ; Valine/biosynthesis* ; Fermentation ; Glucose/metabolism*

OBJECTIVE: To analyze the difference in the gene expression, amino acid and carnitine levels in the cervical secretions between the endometria of pre-receptive and receptive stages, with an aim to provide clues for identifying new molecular markers for endometrial receptivity. METHODS: Fifty nine infertile women treated at the Department of Reproductive Medicine of Linyi People's Hospital from January 6, 2020 to January 31, 2022 were selected as as the study subjects, which were matched with 3 pairs (6 cases) of infertile women preparing for embryo transfer based on factors such as age, body mass index, and length of infertility. Endometrial tissue samples were collected for gene transcription and expression analysis. Twenty five women who had become pregnant through assisted reproductive technology were selected as the control group, and 28 non-pregnant women receiving ovulation monitoring at the Outpatient Department were enrolled as the case group. Status of endometrial receptivity was determined by ultrasonography. In the former group, endometrial tissues were sampled for sequencing, and GO and KEGG database enrichment analysis of differentially expressed genes was carried out. In the latter group, cervical secretions were collected, and amino acid and carnitine levels were measured by mass spectrometry. Statistical analysis was carried out using rank sum test, t test and chi-square test with SPSS v25.0 software. RESULTS: No difference was found in the clinical data of the patients with regard to age, body mass index, infertility years, AMH, FSH, LH, E2, and type of infertility. Compared with the receptive endometrial tissues, there were 100 significantly up-regulated genes and 191 significantly down-regulated genes in the pre-receptive endometrial tissue, with the most significantly altered ones being HLA-DRB5 and MMP10. The biological processes, molecular functions and pathways enriched by more differentially expressed genes in GO and KEGG were mainly immune regulation, cell adhesion and tryptophan metabolism. Analysis of secretion metabolism also revealed a significant difference in the levels of amino acids and carnitine metabolites between the two groups (P < 0.05), in particular those of Alanine, Valine, 3-hydroxybutyrylcarnitine (C4OH) + malonylcarnitine (C3DC)/captoylcarnitine (C10). CONCLUSION A significant difference has been discovered in the levels of gene transcription and protein expression in the endometrial tissues from the pre-receptive and receptive stages. The levels of amino acids and carnitine, such as Alanine, Valine, 3-hydroxybutyryl carnitine (C4OH)+malonyl carnitine (C3DC)/caproyl carnitine (C10), may be associated with the receptive status of the endometrium, though this need to be verified with larger samples.
Pregnancy ; Humans ; Female ; Infertility, Female/genetics* ; Endometrium/metabolism* ; Amino Acids/metabolism* ; Gene Expression ; Carnitine ; Alanine/metabolism* ; Valine/metabolism*

Animals ; Body Weight ; physiology ; Computational Biology ; methods ; Disease Models, Animal ; Doxorubicin ; toxicity ; Fatty Acids, Monounsaturated ; blood ; metabolism ; Glomerulosclerosis, Focal Segmental ; blood ; chemically induced ; metabolism ; Male ; Methoxyhydroxyphenylglycol ; analogs & derivatives ; blood ; metabolism ; Mice ; Mice, Inbred BALB C ; Pyridoxine ; blood ; metabolism ; Valine ; analogs & derivatives ; blood ; metabolism ; Vanillic Acid ; blood ; metabolism

Maple syrup urine disease (MSUD) is a disorder that involves the metabolism of branched chain amino acids, arising from a defect in branched-chain alpha-keto acid dehydrogenase complex. Mutations have been identified in the BCKDHA, BCKDHB, or DBT genes, which encode different subunits of the BCKDH complex. Although encephalopathy and progressive neurodegeneration are its major manifestations, the severity of the disease may range from the severe classic type to milder intermediate variants. We report two Korean siblings with the milder intermediate MSUD who were diagnosed with MSUD by a combination of newborn screening tests using tandem mass spectrometry and family genetic screening for MSUD. At diagnosis, the patients' plasma levels were elevated for leucine, isoleucine, valine, and alloisoleucine, and branched-chain alpha-keto acids and branched-chain alpha-hydroxy acids were detected in their urine. BCKDHA, BCKDHB, and DBT analysis was performed, and two novel mutations were identified in BCKDHB. Our patients were thought to have the milder intermediate variant of MSUD, rather than the classic form. Although MSUD is a typical metabolic disease with poor prognosis, better outcomes can be expected if early diagnosis and prompt management are provided, particularly for milder forms of the disease.
3-Methyl-2-Oxobutanoate Dehydrogenase (Lipoamide) ; Amino Acids ; Diagnosis ; Early Diagnosis ; Genetic Testing ; Humans ; Infant, Newborn ; Isoleucine ; Leucine ; Maple Syrup Urine Disease* ; Mass Screening ; Metabolic Diseases ; Metabolism ; Plasma ; Prognosis ; Siblings* ; Tandem Mass Spectrometry ; Valine

The aim of present study was to explore the vasodilatation mechanism of angiotensin II (AngII) at the molecular level by investigating the effect of AngII on large-conductance Ca²⁺-activated potassium channels (BK(Ca)) in human mesenteric artery smooth muscle cells. The effect of AngII on BK(Ca) was observed by using patch clamp single channel recording technique and amphotericin-perforated whole-cell recording technique. AngII type 1 receptor (AT₁R) and AngII type 2 receptor (AT₂R) mRNA expression in human mesenteric artery was detected by RT-PCR. In cell-attached patch (Vm = +40 mV), AngII (100 nmol/L) had no significant effect on BK(Ca). After pretreatment with Valsartan (a specific inhibitor of AT₁R, 10 μmol/L), 25, 100 and 250 nmol/L AngII stimulated BK(Ca) activity significantly in a dose response manner. After pretreatment of Valsartan, AngII (100 nmol/L) enhanced BK(Ca) open probability (NP(O)) from 0.010 ± 0.003 to 0.039 ± 0.015, decreased the mean close time (T(C)) of BK(Ca) markedly from (2 729.5 ± 808.6) ms to (487.7 ± 182.5) ms (n = 11, P < 0.05) , but AngII had no significant influences on the amplitude (Amp) and the mean open time (T(O)) of BK(Ca). Further PD123,319 (a specific inhibitor of AT₂R) treatment prevented the stimulatory effect of AngII: PD123,319 decreased the NP(O) of BK(Ca) from 0.016 ± 0.003 to 0.004 ± 0.001 (n = 5, P < 0.05), but had no significant influences on Amp, T(O) and T(C) of BK(Ca). In addition, after pretreatment with Valsartan and PD123,319, AngII (100 nmol/L) had no significant effect on BK(Ca). In the amphotericin-perforated whole-cell patch-clamp configuration, after pretreatment with Valsartan, the current density of BK(Ca) at the voltage of -60 - +30 mV had no significant changes before and after adding 100 nmol/L AngII, but the current density of BK(Ca) at the voltage of +40 mV, +50 mV and +60 mV increased significantly after adding 100 nmol/L AngII, from (9.03 ± 2.23) pA/pF, (12.88 ± 2.55) pA/pF and (17.26 ± 2.84) pA/pF to (12.47 ± 2.22) pA/pF, (18.71 ± 2.51) pA/pF and (27.21 ± 3.12) pA/pF (n = 6, P < 0.05), respectively. Using RT-PCR, the AT₁R mRNA and AT₂R mRNA from isolated human mesenteric artery were detected. So we can draw a conclusion, AngII can stimulate BK(Ca) activity in human mesenteric artery smooth muscle cells after pretreatment with Valsartan, which is possibly mediated by AT₂R.
Angiotensin II ; pharmacology ; Humans ; Large-Conductance Calcium-Activated Potassium Channels ; metabolism ; Mesenteric Arteries ; cytology ; Muscle, Smooth, Vascular ; cytology ; Myocytes, Smooth Muscle ; drug effects ; metabolism ; Patch-Clamp Techniques ; Receptor, Angiotensin, Type 1 ; metabolism ; Receptor, Angiotensin, Type 2 ; metabolism ; Tetrazoles ; pharmacology ; Valine ; analogs & derivatives ; pharmacology ; Valsartan ; Vasodilation

BACKGROUNDVascular smooth muscle cell proliferation is an important process in the development of atherosclerosis and is associated with other cellular processes in atherogenesis. Telmisartan is reported to have partial peroxisome proliferator-activated receptor (PPAR)-γ activating properties and has been referred to as selective PPAR modulators, but valsartan just blocks angiotensin II (AngII) type 1 (AT1) receptors. This study aimed to compare the different effects of telmisartan and valsartan on human aortic smooth muscle cells (HASMCs) proliferation.

METHODSAbility of telmisartan and valsartan to inhibit proliferation of HASMCs was evaluated by the Cell Counting Kit-8 (CCK-8) in continuous cell culture. Whether the antiproliferative effects of telmisartan and valsartan depend on their effects on AngII receptors or activating the peroxisome PPAR-γ was also investigated in this study.

RESULTSTelmisartan inhibited proliferation of HASMCs by 52.4% (P < 0.01) at the concentration of 25 µmol/L and the effect depended on the dose of telmisartan, but valsartan had little effect on HASMCs proliferation (P > 0.05) and no dose response. When tested in cells stimulated with AngII, telmisartan had the same inhibition of HASMCs by 59.2% (P < 0.05) and valsartan also inhibited it by 41.6% (P < 0.05). Telmisartan and valsartan had the same effect on down-regulating AT1 receptor expression and telmisartan was superior to valsartan up-regulating AngII type 2 (AT2) receptor expression. Antiproliferative effects of telmisartan were observed when HASMCs were treated with the PPAR-γ antagonist GW9662 but antiproliferative effects of the PPAR-γ activator pioglitazone were not observed.

CONCLUSIONSTelmisartan, but not valsartan, inhibits HASMCs proliferation and has dose-dependent response without stimulation of AngII. AT2 receptor up-regulation of telmisartan contributes to its greater antiproliferative effects than valsartan. Its PPAR-γ activation does not play a critical role in inhibiting HASMCs proliferation.

Benzimidazoles ; pharmacology ; Benzoates ; pharmacology ; Cell Proliferation ; drug effects ; Humans ; Muscle, Smooth, Vascular ; cytology ; metabolism ; Myocytes, Smooth Muscle ; cytology ; drug effects ; PPAR gamma ; metabolism ; Receptor, Angiotensin, Type 1 ; metabolism ; Receptor, Angiotensin, Type 2 ; metabolism ; Tetrazoles ; pharmacology ; Valine ; analogs & derivatives ; pharmacology ; Valsartan

OBJECTIVETo elucidate the effect of valsartan on human glomerular mesangial cells oxidative stress and the expression of the receptor for advanced glycation end products (RAGE) induced by the advanced glycation end-products (AGEs).

METHODSHuman glomerular mesangial cells were treated with advanced glycation end-product-bovine serum albumin (AGE-BSA) in the presence of valsartan. The reactive oxygen species (ROS) in cells were measured by Flow cytometry, and the mRNA of p47 phox, which was the primary subunits of NADPH oxidase, was detected by semi-quantitative reberse transcription polymerase chain reaction (RT-PCR). The mRNA of RAGE was detected by RT-PCR and the RAGE protein was assayed by immunocytochemistry.

RESULTSThe product of ROS, and the expression of p47 phox and RAGE in mesangial cells, which were treated with AGE-BSA in the presence of valsartan, were down-regulated compared with the groups treated with AGE-BSA (P < 0.05). Valsartan dose-dependently and time-dependently inhibited the AGE-elicited overexpression of RAGE, ROS and p47(phox) in mesangial cells.

CONCLUSIONValsartan could inhibit RAGE expression through downregulation of oxidative stress.

Angiotensin II Type 1 Receptor Blockers ; pharmacology ; Antioxidants ; pharmacology ; Glycation End Products, Advanced ; pharmacology ; Humans ; Mesangial Cells ; cytology ; metabolism ; Oxidative Stress ; drug effects ; RNA, Messenger ; genetics ; metabolism ; Receptor for Advanced Glycation End Products ; Receptors, Immunologic ; genetics ; metabolism ; Serum Albumin, Bovine ; pharmacology ; Tetrazoles ; pharmacology ; Valine ; analogs & derivatives ; pharmacology ; Valsartan

BACKGROUNDThe development of diabetic cardiomyopathy is multifactorial. Insulin resistance (IR) and excessive activity of the renin-angiotensin system are confirmed reasons for diabetic cardiomyopathy. Renin-angiotensin system (RAS) inhibitors can reduce tissue Ang II levels, with beneficial effects on cardiovascular function. Therefore, in type-2 diabetes mellitus (T2DM), blockade of the RAS may have the function of protecting against diabetic cardiomyopathy through increasing insulin sensitivity and inhibiting excessive activity of RAS. However, this has not been confirmed.

METHODSThe effect of valsartan, an angiotensin receptor blocker (ARB), on diabetic cardiomyopathy in the presence of T2DM was studied. Wistar rats with T2DM and T2DM treated with valsartan were studied. Glucose infusion rates (GIR), index of IR, heart weight, the heart weight-to-body weight ratio (HW/BW), myocardial apoptotic index, cardiac hydroxyprolin content, and cardiac tissue collagen type I and collagen type III content were measured.

RESULTSGIR in T2DM rats and T2DM rats treated with valsartan decreased (P < 0.01). In T2DM rats treated with valsartan, heart weight, myocardial apoptotic index, cardiac hydroxyprolin content, and cardiac tissue collagen type I and collagen type III content were higher than in control rats, but lower than in T2DM rats. In rats with T2DM, GIR was negatively and significantly correlated with all the variables. However, in T2DM rats treated with valsartan or normal control rats, none of the correlations was significant.

CONCLUSIONSIn the presence of T2DM, diabetic cardiomyopathy is related with IR. Valsartan can not alleviate IR, but can protect against diabetic cardiomyopathy and remove the correlation between IR and diabetic cardiomyopathy.

Angiotensin II Type 1 Receptor Blockers ; therapeutic use ; Animals ; Apoptosis ; Collagen Type I ; analysis ; Collagen Type III ; analysis ; Diabetes Mellitus, Type 2 ; complications ; drug therapy ; metabolism ; Diabetic Cardiomyopathies ; prevention & control ; Hydroxyproline ; analysis ; Insulin Resistance ; Male ; Myocardium ; chemistry ; pathology ; Rats ; Rats, Wistar ; Tetrazoles ; therapeutic use ; Valine ; analogs & derivatives ; therapeutic use ; Valsartan

OBJECTIVETo study the effect of angiotensin II on phosphoinositide-3 kinase/Akt cascade in cultured fibroblasts derived from patients with hypertrophic scars.

METHODSThe expression of AT1 and AT2 receptor was detected by immunofluorescence staining. Cultured human skin fibroblasts were treated with Ang II (10(-9) - 10(-7) mol/L), with or without an AT1 receptor blocker, valsartan or an AT2 receptor antagonist, PD123319. The phosphorylation of Akt was detected by western blotting, and PI3K activity was measured by Assay of PI3-K activity.

RESULTSImmunofluorescence staining showed that cultured fibroblasts derived from hypertrophic scars expressed both AT1 and AT2 receptors. Ang II increased Akt phosphorylation and PI3K activity in cultured hypertrophic scar fibroblasts in a dose- and time-dependent manner. Additionally, Ang II-induced Akt phosphorylation was blocked by wortmannin, a PI3-K inhibitor. This Ang II-activated PI3-K/Akt cascade was significantly inhibited by valsartan, an AT1 receptor specific blocker (P<0.05), whereas enhanced by PD123319, an AT2 receptor antagonist (P<0.05).

CONCLUSIONThese results indicate that Ang II receptors regulates PI3-K/Akt cascade of hypertrophic scars fibroblasts via AT1 and AT2.

Angiotensin II ; pharmacology ; Angiotensin II Type 1 Receptor Blockers ; pharmacology ; Angiotensin II Type 2 Receptor Blockers ; Cells, Cultured ; Cicatrix, Hypertrophic ; metabolism ; pathology ; Fibroblasts ; cytology ; drug effects ; metabolism ; Humans ; Imidazoles ; pharmacology ; Phosphatidylinositol 3-Kinases ; metabolism ; Proto-Oncogene Proteins c-akt ; metabolism ; Pyridines ; pharmacology ; Receptor, Angiotensin, Type 1 ; Signal Transduction ; Tetrazoles ; pharmacology ; Valine ; analogs & derivatives ; pharmacology ; Valsartan

This experiment on rats was aimed to investigate the expression of intermedin (IMD) in hypertrophic cardiac myoctye of renal vascular hypertension induced by incomplete ligation of the left renal artery, and so to detect and compare the changes of the expression after administration of Valsartan, Amlodipine and Enalapril respectively. The criterion for standard modeling was systolic pressure > or = 140 mmHg. At 4 weeks after successful modeling, 60 SD male rats were randomly divided into 5 groups, namely the hypertrophy group, the 3 drug-treatment groups, and the sham-operation group as control. Blood pressure, left ventricular mass index (LVMI), and the left ventricular mean transverse diameter of myocardial cell (LVTDM) were investigated at the 10th week after model establishment. Gene expression of IMD mRNA was detected by reverse transcription-polymerase chain reaction (RT-PCR), and the optical density of the band was measured by use of the Gel Documentation System. The ratio of IMD mRNA to beta-actin mRNA was considered the relative amount of IMD. When compared with control, the blood pressure increased significantly in the hypertrophy group. There was no statistically significant difference between the treatment groups. No significant difference in heart rate was noted at 4 weeks after operation in all groups. LVMI and LVTDM levels were significantly higher in the hypertrophy group than in the other groups; LVMI and LVTDM levels showed no significant difference among the treatment groups but they were obviously higher than those of the Sham-operation group. The gene expression of IMD mRNA in the hypertrophy group was upregulated in the myocardium, when compared with that in the other groups. Meanwhile, although IMD mRNA in the treament groups was higher than that in the Sham-operation group, no statistically significant difference of myocardial IMD mRNA was found between the treament groups. These results suggested that, in this experiment, intracardiac IMD mRNA was upregulated and could participate in the regulation of cardiac remodeling in renal vascular hypertension-induced cardiac hypertrophy. This upregulation could improve the pathologic and physiologic process of cardiac hypertrophy, and could associate with the pressure loading or myocardia hypertrophy. However, the change did not display any difference that could be attributed to the variety of hypotensive drugs.
Adrenomedullin ; genetics ; metabolism ; Amlodipine ; therapeutic use ; Animals ; Antihypertensive Agents ; therapeutic use ; Cardiomegaly ; etiology ; metabolism ; Enalapril ; therapeutic use ; Hypertension, Renovascular ; complications ; drug therapy ; metabolism ; Male ; Myocardium ; metabolism ; Neuropeptides ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Tetrazoles ; therapeutic use ; Valine ; analogs & derivatives ; therapeutic use ; Valsartan