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1.
Small ; 20(2): e2305670, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37658521

ABSTRACT

N-type Mg3 Sb2 -based thermoelectric materials show great promise in power generation due to their mechanical robustness, low cost of Mg, and high figure of merit (ZT) over a wide range of temperatures. However, their poor thermal stability hinders their practical applications. Here, MgB2 is introduced to improve the thermal stability of n-type Mg3 Sb2 . Enabled by MgB2 decomposition, extra Mg can be released into the matrix for Mg compensation thermodynamically, and secondary phases of Mg─B compounds can kinetically prevent Mg diffusion along grain boundaries. These synergetic effects inhibit the formation of Mg vacancies at elevated temperatures, thereby enhancing the thermal stability of n-type Mg3 Sb2 . Consequently, the Mg3.05 (Sb0.75 Bi0.25 )1.99 Te0.01 (MgB2 )0.03 sample exhibits negligible variation in thermoelectric performance during the 120-hour continuous measurement at 673 K. Moreover, the ZT of n-type Mg3 Sb2 can be maintained by adding MgB2 , reaching a high average ZT of ≈1.1 within 300-723 K. An eight-pair Mg3 Sb2 -GeTe-based thermoelectric device is also fabricated, achieving an energy conversion efficiency of ≈5.7% at a temperature difference of 438 K with good thermal stability. This work paves a new way to enhance the long-term thermal stability of n-type Mg3 Sb2 -based alloys and other thermoelectrics for practical applications.

2.
Small ; 19(44): e2303840, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37381087

ABSTRACT

N-type Mg3 (Bi, Sb)2 -based thermoelectric (TE) alloys show great promise for solid-state power generation and refrigeration, owing to their excellent figure-of-merit (ZT) and using cheap Mg. However, their rigorous preparation conditions and poor thermal stability limit their large-scale applications. Here, this work develops an Mg compensating strategy to realize n-type Mg3 (Bi, Sb)2 by a facile melting-sintering approach. "2D roadmaps" of TE parameters versus sintering temperature and time are plotted to understand the Mg-vacancy-formation and Mg-diffusion mechanisms. Under this guidance, high weight mobility of 347 cm2  V-1  s-1 and power factor of 34 µW cm-1  K-2 can be obtained for Mg3.05 Bi1.99 Te0.01 , and a peak ZT≈1.55 at 723 K and average ZT≈1.25 within 323-723 K can be obtained for Mg3.05 (Sb0.75 Bi0.25 )1.99 Te0.01 . Moreover, this Mg compensating strategy can also improve the interfacial connecting and thermal stability of corresponding Mg3 (Bi, Sb)2 /Fe TE legs. As a consequence, this work fabricates an 8-pair Mg3 Sb2 -GeTe-based power-generation device reaching an energy conversion efficiency of ≈5.0% at a temperature difference of 439 K, and a one-pair Mg3 Sb2 -Bi2 Te3 -based cooling device reaching -10.7 °C at the cold side. This work paves a facile way to obtain Mg3 Sb2 -based TE devices at low cost and also provides a guide to optimize the off-stoichiometric defects in other TE materials.

3.
Zhonghua Nan Ke Xue ; 29(9): 799-803, 2023 Sep.
Article in Zh | MEDLINE | ID: mdl-38639591

ABSTRACT

OBJECTIVE: To explore the mechanism of Shenrong pills in improving oligoasthenospermia by inhibiting oxidative stress-induced Leydig cell apoptosis in mouse testis. METHODS: The oxidative stress model of mouse Leydig cells (TM3) was induced by 3% hydrogen peroxide (H2O2) of 600 µmol/L, and then TM3 cells were treated with 7.5%, 10% and 12.5% serum containing Shenrong pills, respectively. TM3 cells were divided into normal control group, model group, and low, medium and high dose groups of Shenrong pills containing serum. The cell viability of TM3 after treatment was detected by CCK-8 method, reactive oxygen species (ROS) were detected by DCFH probe method, and SOD-1, CAT, GSH-px, MDA and LPO in cell lysates were detected by ELISA method. The changes of apoptosis-related proteins Bcl-2, Bax in cell lysates were detected by Western Blot. RESULTS: After H2O2 treatment, compared with normal control group, cell viability was significantly decreased (P< 0.01), MDA and LPO contents were significantly increased (P<0.01), SOD-1, CAT and GSH-px contents were significantly decreased (P<0.01). Reactive oxygen species (ROS) were significantly increased, the relative expression ratio of Bcl-2 protein was significantly decreased (P<0.01, P<0.05), and the relative expression of Bax protein was increased. After the administration of Shenrong pills containing serum, the above indexes were reversed to varying degrees. CONCLUSION: Shenrong pills can resist oxidative stress, inhibit the apoptosis of TM3 cells in mice, maintain high levels of testosterone required for spermatogenic cells, and improve the sperm quality of mice with oligonasthenospermia.


Subject(s)
Hydrogen Peroxide , Leydig Cells , Mice , Animals , Male , Reactive Oxygen Species/metabolism , Hydrogen Peroxide/pharmacology , Semen/metabolism , Oxidative Stress , Proto-Oncogene Proteins c-bcl-2/metabolism , Proto-Oncogene Proteins c-bcl-2/pharmacology , Apoptosis
4.
Mar Drugs ; 20(7)2022 Jun 26.
Article in English | MEDLINE | ID: mdl-35877710

ABSTRACT

Previous studies found that both oral and topical administration of enzymatic digestion products < 3 K Da ultrafiltration fractions of Pinctada martensii mantle (PMPs) had pro-healing effects. Thus, we further purified them by Sephadex-G25 and screened them by cellular assays to obtain Pinctada martensii purified peptides (PMPPs). In this study, we explored the mechanism of PMPPs on wound healing by in vivo, in vitro, and in silico experiments. LC-MS/MS results showed that PMPPs consisted of 33 peptides with molecular weights ranging from 758.43 to 2014.04 Da, and the characteristic peptide was Leu-Asp. The results of cellular assays showed that PMPPs promoted the proliferation of human skin fibroblasts (HSF) (135%) and human immortalized keratinocyte (HaCaT) cells (125%) very significantly at 12.5 µg/mL. The in vivo results showed that PMPPs could achieve scarless healing by inhibiting the inflammatory response, accelerating the epithelialization process, and regulating collagen I/III ratio. The optimal peptide sequence FAFQAEIAQLMS of PMPPs was screened for key protein receptors in wound healing (EGFR1, FGFR1, and MMP-1) with the help of molecular docking technique, which also showed to be the key pro-healing active peptide sequence. Therefore, it may provide a therapeutic strategy with great potential for wound healing.


Subject(s)
Pinctada , Animals , Chromatography, Liquid , Humans , Molecular Docking Simulation , Peptides/chemistry , Pinctada/chemistry , Tandem Mass Spectrometry , Wound Healing
5.
Mar Drugs ; 20(12)2022 Nov 28.
Article in English | MEDLINE | ID: mdl-36547896

ABSTRACT

This study aimed to purify and identify antiphotoaging peptides from oyster (Crassostrea hongkongensis) protein enzymatic hydrolysates (OPEH) and to investigate the possible mechanism underlying its antiphotoaging effect. Multiple methods (Ultrafiltration, G25 Chromatography, RP-HPLC, and LC/MS/MS) had been used for this purpose, and eventually, two peptides, including WNLNP and RKNEVLGK, were identified. Particularly, WNLNP exerted remarkable antiphotoaging effect on the UVB-irradiated HaCaT photoaged cell model in a dose-dependent manner. WNLNP exerted its protective effect mainly through inhibiting ROS production, decreasing MMP-1 expression, but increasing extracellular pro-collagen I content. Furthermore, WNLNP downregulated p38, JNK, ERK, and p65 phosphorylation in the MAPK/NF-κB signaling pathway and attenuated bax over-expressions but reversed bcl-2 reduction in UVB- irradiated HaCaT cells. The molecular docking analysis showed that WNLNP forms five and seven hydrogen bonds with NF-κB (p65) and MMP-1, respectively. This study suggested that a pentapeptide WNLNP isolated from OPEH had great potential to prevent and regulate skin photoaging.


Subject(s)
Crassostrea , Oligopeptides , Skin Aging , Animals , Humans , Crassostrea/chemistry , HaCaT Cells , Matrix Metalloproteinase 1/metabolism , Molecular Docking Simulation , NF-kappa B/metabolism , Skin Aging/drug effects , Tandem Mass Spectrometry , Ultraviolet Rays/adverse effects , Oligopeptides/chemistry , Oligopeptides/isolation & purification , Oligopeptides/pharmacology
6.
Small ; 17(42): e2104067, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34541782

ABSTRACT

Powder metallurgy introduces small structures of high-density grain boundaries into Bi2 Te3 -based alloys, which promises to enhance their mechanical and thermoelectric performance. However, due to the strong donor-like effect induced by the increased surface, Te vacancies form in the powder-metallurgy process. Hence, the as-sintered n-type Bi2 Te3 -based alloys show a lower figure of merit (ZT) value than their p-type counterparts and the commercial zone-melted (ZM) ingots. Here, boron is added to one-step-sintered n-type Bi2 Te3 -based alloys to inhibit grain growth and to suppress the donor-like effect, simultaneously improving the mechanical and thermoelectric (TE) performance. Due to the alleviated donor-like effect and the carrier mobility maintained in our n-type Bi2 Te2.7 Se0.3 alloys upon the addition of boron, the maximum and average ZT values within 298-473 K can be enhanced to 1.03 and 0.91, respectively, which are even slightly higher than that of n-type ZM ingots. Moreover, the addition of boron greatly improves the mechanical strength such as Vickers hardness and compressive strength due to the synergetic effects of Hall-Petch grain-boundary strengthening and boron dispersion strengthening. This facile and cost-effective grain boundary engineering by adding boron facilitates the practical application of Bi2 Te3 -based alloys and can also be popularized in other thermoelectric materials.

7.
Mar Drugs ; 19(10)2021 Oct 09.
Article in English | MEDLINE | ID: mdl-34677464

ABSTRACT

Peptides from oyster hydrolysate (OPs) have a variety of biological activities. However, its protective effect and exact mechanism on testicular injury remain poorly understood. This study aimed to evaluate the protective effect of OPs on triptolide (TP)-induced testis damage and spermatogenesis dysfunction and investigate its underlying mechanism. In this work, the TP-induced testis injury model was created while OPs were gavaged in mice for 4 weeks. The results showed that OPs significantly improved the sperm count and motility of mice, and alleviated the seminiferous tubule injury. Further study showed that OPs decreased malonaldehyde (MDA) level and increased antioxidant enzyme (SOD and GPH-Px) activities, attenuating oxidative stress and thereby reducing the number of apoptotic cells in the testis. In addition, OPs improved the activities of enzymes (LDH, ALP and ACP) related to energy metabolism in the testis and restored the serum hormone level of mice to normal. Furthermore, OPs promoted the expression of Nrf2 protein, and then increased the expression of antioxidant enzyme regulatory protein (HO-1 and NQO1) in the testis. OPs inhibited JNK phosphorylation and Bcl-2/Bax-mediated apoptosis. In conclusion, OPs have a protective effect on testicular injury and spermatogenesis disorders caused by TP, suggesting the potential protection of OPs on male reproduction.


Subject(s)
Crassostrea , Peptides/pharmacology , Protective Agents/pharmacology , Spermatogenesis/drug effects , Testis/drug effects , Animals , Aquatic Organisms , Disease Models, Animal , Diterpenes , Epoxy Compounds , Male , Mice , Mice, Inbred ICR , Phenanthrenes
8.
Molecules ; 26(5)2021 Mar 04.
Article in English | MEDLINE | ID: mdl-33806637

ABSTRACT

Marine collagen peptides have high potential in promoting skin wound healing. This study aimed to investigate wound healing activity of collagen peptides derived from Sipunculus nudus (SNCP). The effects of SNCP on promoting healing were studied through a whole cortex wound model in mice. Results showed that SNCP consisted of peptides with a molecular weight less than 5 kDa accounted for 81.95%, rich in Gly and Arg. SNCP possessed outstanding capacity to induce human umbilical vein endothelial cells (HUVEC), human immortalized keratinocytes (HaCaT) and human skin fibroblasts (HSF) cells proliferation and migration in vitro. In vivo, SNCP could markedly improve the healing rate and shorten the scab removal time, possessing a scar-free healing effect. Compared with the negative control group, the expression level of tumor necrosis factor-α, interleukin-1ß and transforming growth factor-ß1 (TGF-ß1) in the SNCP group was significantly down-regulated at 7 days post-wounding (p < 0.01). Moreover, the mRNA level of mothers against decapentaplegic homolog 7 (Smad7) in SNCP group was up-regulated (p < 0.01); in contrast, type II TGF-ß receptors, collagen I and α-smooth muscle actin were significantly down-regulated at 28 days (p < 0.01). These results indicate that SNCP possessed excellent activity of accelerating wound healing and inhibiting scar formation, and its mechanism was closely related to reducing inflammation, improving collagen deposition and recombination and blockade of the TGF-ß/Smads signal pathway. Therefore, SNCP may have promising clinical applications in skin wound repair and scar inhibition.


Subject(s)
Cicatrix/drug therapy , Collagen/pharmacology , Keratinocytes/drug effects , Peptide Fragments/isolation & purification , Peptide Fragments/pharmacology , Polychaeta/chemistry , Skin/drug effects , Wound Healing/drug effects , Animals , Cicatrix/metabolism , Collagen/chemistry , Humans , Keratinocytes/metabolism , Male , Mice , Peptide Fragments/chemistry , Signal Transduction , Skin/metabolism
9.
Nucleic Acids Res ; 46(15): 7716-7730, 2018 09 06.
Article in English | MEDLINE | ID: mdl-29982688

ABSTRACT

Linker histone H1 has a key role in maintaining higher order chromatin structure and genome stability, but how H1 functions in these processes is elusive. Here, we report that acetylation of lysine 85 (K85) within the H1 globular domain is a critical post-translational modification that regulates chromatin organization. H1K85 is dynamically acetylated by the acetyltransferase PCAF in response to DNA damage, and this effect is counterbalanced by the histone deacetylase HDAC1. Notably, an acetylation-mimic mutation of H1K85 (H1K85Q) alters H1 binding to the nucleosome and leads to condensed chromatin as a result of increased H1 binding to core histones. In addition, H1K85 acetylation promotes heterochromatin protein 1 (HP1) recruitment to facilitate chromatin compaction. Consequently, H1K85 mutation leads to genomic instability and decreased cell survival upon DNA damage. Together, our data suggest a novel model whereby H1K85 acetylation regulates chromatin structure and preserves chromosome integrity upon DNA damage.


Subject(s)
Chromatin/metabolism , DNA Damage , Genomic Instability , Histones/metabolism , Lysine/metabolism , A549 Cells , Acetylation , Cell Line, Tumor , Cell Survival/genetics , Chromatin/genetics , Chromobox Protein Homolog 5 , Chromosomal Proteins, Non-Histone/genetics , Chromosomal Proteins, Non-Histone/metabolism , HCT116 Cells , HEK293 Cells , HeLa Cells , Histones/genetics , Humans , Lysine/genetics , Mutation , Nucleosomes/genetics , Nucleosomes/metabolism , p300-CBP Transcription Factors/genetics , p300-CBP Transcription Factors/metabolism
10.
Mar Drugs ; 18(6)2020 May 31.
Article in English | MEDLINE | ID: mdl-32486363

ABSTRACT

Chronic exposure to ultraviolet B (UVB) irradiation is a major cause for skin photoaging. UVB induces damage to skin mainly by oxidative stress, inflammation, and collagen degradation. This paper investigated the photo-protective effects of peptides from oyster (Crassostrea hongkongensis) protein hydrolysates (OPs) by topical application on the skin of UVB-irradiated mice. Results from mass spectrometry showed that OPs consisted of peptides with a molecular weight range of 302.17-2936.43 Da. In vivo study demonstrated that topical application of OPs on the skin significantly alleviated moisture loss, epidermal hyperplasia, as well as degradation of collagen and elastin fibers caused by chronic UVB irradiation. In this study, OPs treatment promoted antioxidant enzymes (SOD and GPH-Px) activities, while decreased malondialdehyde (MDA) level in the skin. In addition, OPs treatment significantly decreased inflammatory cytokines (IL-1ß, IL-6, TNF-α) content, and inhibited inflammation related (iNOS, COX-2) protein expression in the skin. Via inhibiting metalloproteinase 1(MMP1) expression, OPs treatment markedly decreased the degradation of collagen and elastin fibers as well as recovered the altered arrangement of extracellular matrix network in the dermis of skin. Our study demonstrated for the first time that OPs protected against UVB induced skin photodamage by virtue of its antioxidative and anti-inflammatory properties, as well as regulating the abnormal expression of MMP-1. The possible molecular mechanism underlying OPs anti-photoaging is possibly related to downregulating of the MAPK/NF-κB signaling pathway, while promoting TGF-ß production in the skin.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Crassostrea/chemistry , Protein Hydrolysates/pharmacology , Skin Aging/drug effects , Ultraviolet Rays , Animals , Disease Models, Animal , Female , Mice , Mice, Inbred Strains
11.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 37(3): 460-468, 2020 Jun 25.
Article in Zh | MEDLINE | ID: mdl-32597088

ABSTRACT

In order to explore the effect of Sipunculus nudus extract (SNE) on skin wound healing in mice and its mechanism, hemostasis effect of SNE was measured, the mouse skin wound model was established by full-thickness excision. The morphological changes of the wound were observed after the treatment with SNE and the healing rate was measured. The changes of wound histology were observed by hematoxylin eosin (HE) staining, Masson staining and transmission electron microscope (TEM). The expression of cell factors and related proteins was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Results showed that the SNE possessed hemostatic function. SNE could obviously improve the healing rate of wound in mouse and shorten time of scab removal compared with the none-treatment (NT) group ( P < 0.05).The pathological histology analysis results showed complete epidermal regeneration, with remarkable capillary and collagen fiber observed in the SNE group. The expression level of tumor necrosis factor-α (TNF -α), interleukin-1ß (IL-1ß) and transforming growth factor-ß1 (TGF-ß1) in SNE group was significantly lower than that of the NT group on 7 d ( P < 0.05). Moreover, compared with the NT group, the gene expressions level of Smad7 was significantly increased and the level of type II TGF-ß receptors (TGF-ßRII), collagen I (COL1A1) and α-smooth muscle actin (α-SMA) were significantly reduced in the SNE group on 28 d ( P < 0.05), but the difference was not statistically significant compared to Yunnanbaiyao group (PC group) ( P > 0.05). These results indicated that SNE possessed obvious activity of accelerating wound healing and inhibiting scar formation, and its mechanism was closely related to hemostatic function, regulation of inflammatory factors, collagen deposition, collagen fiber remodeling and intervening TGF-ß/Smads signal pathway. Therefore, SNE may have promising clinical applications in skin wound repair and scar inhibition.


Subject(s)
Skin , Wound Healing , Acceleration , Animals , Annelida , Collagen , Mice , Transforming Growth Factor beta1
12.
Fish Shellfish Immunol ; 89: 623-631, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30991151

ABSTRACT

Antimicrobial peptides (AMPs) participate in immune defenses of invertebrate, vertebrate and plant species. As a kind of AMPs, penaeidins play important roles in innate immunity of shrimp. In this study, two penaeidin homologues termed FmPEN3 and FmPEN5 were cloned and identified from Fenneropenaeus merguiensis for the first time. The complete open reading frames (ORFs) of FmPEN3 and FmPEN5 were 216 bp and 240 bp, encoding 71 and 79 amino acids, respectively. Both FmPEN3 and FmPEN5 contain an N-terminal proline-rich domain (PRD) and a C-terminal cysteine-rich domain (CRD). The genome structure of FmPEN3 and FmPEN5 genes both consist of 2 exons and 1 intron. qPCR analysis showed that FmPEN3 was constitutively expressed but FmPEN5 transcripts were found only in hemocytes, gills, epidermis, nerve and pyloric cecum. The FmPEN3 and FmPEN5 expression were responsive to Vibrio parahaemolyticus and Micrococcus lysodeikticus infection and their transcription levels were downregulated by RNAi silencing of the transcription factors FmDorsal and FmRelish. In addition, recombinant proteins of FmPEN3 (rFmPEN3) and FmPEN5 (rFmPEN5) were successfully expressed in E. coli. The antibacterial assays revealed that rFmPEN3 and rFmPEN5 could inhibit the growth of M. lysodeikticus but only rFmPEN5 could inhibit the growth of V. parahaemolyticus in vitro. In summary, the results presented in this study indicated the functions of FmPEN3 and FmPEN5 played in anti-bacterial immunity of F. merguiensis, providing some insights into the function of AMPs in shrimp.


Subject(s)
Gene Expression Regulation/immunology , Immunity, Innate/genetics , Penaeidae/genetics , Penaeidae/immunology , Peptides/genetics , Peptides/immunology , Amino Acid Sequence , Animals , Arthropod Proteins/chemistry , Arthropod Proteins/genetics , Arthropod Proteins/immunology , Base Sequence , Gene Expression Profiling , Micrococcus/physiology , Peptides/chemistry , Phylogeny , Sequence Alignment , Vibrio parahaemolyticus/physiology
13.
Mar Drugs ; 17(12)2019 Dec 12.
Article in English | MEDLINE | ID: mdl-31842313

ABSTRACT

Skin wound healing, especially chronic wound healing, is a common challenging clinical problem. It is urgent to broaden the sources of bioactive substances that can safely and efficiently promote skin wound healing. This study aimed to observe the effects of active peptides (APs) of the mantle of Pinctada martensii on wound healing. After physicochemical analysis of amino acids and mass spectrometry of APs, the effect of APs on promoting healing was studied through a whole cortex wound model on the back of mice for 18 consecutive days. The results showed that APs consisted of polypeptides with molecular weights in the range 302.17-2936.43 Da. The content of polypeptides containing 2-15 amino acids accounted for 73.87%, and the hydrophobic amino acids accounted for 56.51%. Results of in vitro experimentation showed that mice in APs-L group which were fed a low dose of APs (0.5 g/kg bw) had a shortened epithelialization time due to a shortening inflammatory period (p < 0.05). Mechanistically, this relied on its specific ability to promote the proliferation of CD31, FGF and EGF which accelerated the percentage of wound closure. Moreover, the APs-L group mice had enhanced collagen synthesis and increased type III collagen content in their wounds through a TGF-ß/Smad signaling pathway (p > 0.05). Consequently, scar formation was inhibited and wound healing efficiency was significantly improved. These results show that the APs of Pinctada martensii promote dermal wound healing in mice and have tremendous potential for development and utilization in skin wound healing.


Subject(s)
Peptides/pharmacology , Pinctada/chemistry , Skin Diseases/drug therapy , Wound Healing/drug effects , Administration, Oral , Animals , Cicatrix/prevention & control , Collagen/metabolism , Disease Models, Animal , Male , Mice , Molecular Weight , Peptides/administration & dosage , Peptides/isolation & purification , Skin/drug effects , Skin/pathology , Skin Diseases/pathology
14.
Molecules ; 24(23)2019 Nov 21.
Article in English | MEDLINE | ID: mdl-31766365

ABSTRACT

Skin wound healing, especially chronic wound healing, is a common challenging clinical problem. It is urgent to broaden the sources of bioactive substances that can safely and efficiently promote skin wound healing. This study aimed to observe the effects of small molecular peptides (SMPs) of the mantle of Pinctada martensii on wound healing. After physicochemical analysis of amino acids and mass spectrometry of SMPs, the effect of SMPs on promoting healing was studied through a whole cortex wound model on the back of mice for 18 consecutive days. The results showed that SMPs consisted of polypeptides with a molecular weight of 302.17-2936.43 Da. The content of polypeptides containing 2-15 amino acids accounted for 73.87%, and the hydrophobic amino acids accounted for 56.51%. Results of in vitro experimentation showed that SMPs possess a procoagulant effect, but no antibacterial activity. Results of in vivo experiments indicated that SMPs inhibit inflammatory response by secretion of anti-inflammatory factor IL-10 during the inflammatory phase; during the proliferative phase, SMPs promote the proliferation of fibroblasts and keratinocytes. The secretion of transforming growth factor-ß1 and cyclin D1 accelerates the epithelialization and contraction of wounds. In the proliferative phase, SMPs effectively promote collagen deposition and partially inhibit superficial scar hyperplasia. These results show that SMPs promotes dermal wound healing in mice and have a tremendous potential for development and utilization in skin wound healing.


Subject(s)
Keratinocytes/physiology , Peptides/pharmacology , Pinctada/metabolism , Skin/cytology , Small Molecule Libraries/pharmacology , Wound Healing/drug effects , Animals , Bacteria/drug effects , Blood Coagulation/drug effects , Cell Proliferation , Cells, Cultured , Cytokines/metabolism , Keratinocytes/cytology , Keratinocytes/drug effects , Male , Mice , Skin/drug effects , Wounds and Injuries/drug therapy , Wounds and Injuries/metabolism , Wounds and Injuries/pathology
15.
J Biol Chem ; 292(32): 13296-13311, 2017 08 11.
Article in English | MEDLINE | ID: mdl-28655758

ABSTRACT

Sirtuin 7 (SIRT7), a member of the NAD+-dependent class III histone deacetylases, is involved in the regulation of various cellular processes and in resisting various stresses, such as hypoxia, low glucose levels, and DNA damage. Interestingly, SIRT7 is linked to the control of glycolysis, suggesting a role in glucose metabolism. Given the important roles of SIRT7, it is critical to clarify how SIRT7 activity is potentially regulated. It has been reported that some transcriptional and post-transcriptional regulatory mechanisms are involved. However, little is known how SIRT7 is regulated by the post-translational modifications. Here, we identified ubiquitin-specific peptidase 7 (USP7), a deubiquitinase, as a negative regulator of SIRT7. We showed that USP7 interacts with SIRT7 both in vitro and in vivo, and we further demonstrated that SIRT7 undergoes endogenous Lys-63-linked polyubiquitination, which is removed by USP7. Although the USP7-mediated deubiquitination of SIRT7 had no effect on its stability, the deubiquitination repressed its enzymatic activity. We also showed that USP7 coordinates with SIRT7 to regulate the expression of glucose-6-phosphatase catalytic subunit (G6PC), a gluconeogenic gene. USP7 depletion by RNA interference increased both G6PC expression and SIRT7 enzymatic activity. Moreover, SIRT7 targeted the G6PC promoter through the transcription factor ELK4 but not through forkhead box O1 (FoxO1). In summary, SIRT7 is a USP7 substrate and has a novel role as a regulator of gluconeogenesis. Our study may provide the basis for new clinical approaches to treat metabolic disorders related to glucose metabolism.


Subject(s)
Gene Expression Regulation, Enzymologic , Glucose-6-Phosphatase/metabolism , Promoter Regions, Genetic , Protein Processing, Post-Translational , Sirtuins/metabolism , Ubiquitin Thiolesterase/metabolism , ets-Domain Protein Elk-4/metabolism , Amino Acid Substitution , Cell Line, Tumor , Gene Deletion , Gluconeogenesis , Glucose-6-Phosphatase/antagonists & inhibitors , Glucose-6-Phosphatase/genetics , HEK293 Cells , Humans , Hydrolysis , Lysine/metabolism , Mutation , Peptide Fragments/antagonists & inhibitors , Peptide Fragments/genetics , Peptide Fragments/metabolism , Protein Interaction Domains and Motifs , Protein Subunits/genetics , Protein Subunits/metabolism , RNA Interference , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/metabolism , Sirtuins/antagonists & inhibitors , Sirtuins/genetics , Substrate Specificity , Ubiquitin Thiolesterase/antagonists & inhibitors , Ubiquitin Thiolesterase/genetics , Ubiquitin-Specific Peptidase 7 , Ubiquitination , ets-Domain Protein Elk-4/genetics
16.
Proteomics ; 17(13-14)2017 Jul.
Article in English | MEDLINE | ID: mdl-28556401

ABSTRACT

SIRT7 is a class III histone deacetylase that is involved in numerous cellular processes. Only six substrates of SIRT7 have been reported thus far, so we aimed to systematically identify SIRT7 substrates using stable-isotope labeling with amino acids in cell culture (SILAC) coupled with quantitative mass spectrometry (MS). Using SIRT7+/+ and SIRT7-/- mouse embryonic fibroblasts as our model system, we identified and quantified 1493 acetylation sites in 789 proteins, of which 261 acetylation sites in 176 proteins showed ≥2-fold change in acetylation state between SIRT7-/- and SIRT7+/+ cells. These proteins were considered putative SIRT7 substrates and were carried forward for further analysis. We then validated the predictive efficiency of the SILAC-MS experiment by assessing substrate acetylation status in vitro in six predicted proteins. We also performed a bioinformatic analysis of the MS data, which indicated that many of the putative protein substrates were involved in metabolic processes. Finally, we expanded our list of candidate substrates by performing a bioinformatics-based prediction analysis of putative SIRT7 substrates, using our list of putative substrates as a positive training set, and again validated a subset of the proteins in vitro. In summary, we have generated a comprehensive list of SIRT7 candidate substrates.


Subject(s)
Embryo, Mammalian/metabolism , Fibroblasts/metabolism , Proteome/analysis , Sirtuins/physiology , Tandem Mass Spectrometry/methods , Acetylation , Amino Acid Motifs , Animals , Cells, Cultured , Chromatography, High Pressure Liquid/methods , Embryo, Mammalian/cytology , Fibroblasts/cytology , Mice , Mice, Knockout , Proteomics , Substrate Specificity
17.
Proc Natl Acad Sci U S A ; 111(29): 10684-9, 2014 Jul 22.
Article in English | MEDLINE | ID: mdl-25009184

ABSTRACT

In mammalian cells, tumor suppressor p53 plays critical roles in the regulation of glucose metabolism, including glycolysis and oxidative phosphorylation, but whether and how p53 also regulates gluconeogenesis is less clear. Here, we report that p53 efficiently down-regulates the expression of phosphoenolpyruvate carboxykinase (PCK1) and glucose-6-phosphatase (G6PC), which encode rate-limiting enzymes in gluconeogenesis. Cell-based assays demonstrate the p53-dependent nuclear exclusion of forkhead box protein O1 (FoxO1), a key transcription factor that mediates activation of PCK1 and G6PC, with consequent alleviation of FoxO1-dependent gluconeogenesis. Further mechanistic studies show that p53 directly activates expression of the NAD(+)-dependent histone deacetylase sirtuin 6 (SIRT6), whose interaction with FoxO1 leads to FoxO1 deacetylation and export to the cytoplasm. In support of these observations, p53-mediated FoxO1 nuclear exclusion, down-regulation of PCK1 and G6PC expression, and regulation of glucose levels were confirmed in C57BL/J6 mice and in liver-specific Sirt6 conditional knockout mice. Our results provide insights into mechanisms of metabolism-related p53 functions that may be relevant to tumor suppression.


Subject(s)
Cell Nucleus/metabolism , Forkhead Transcription Factors/metabolism , Gluconeogenesis/genetics , Sirtuins/metabolism , Tumor Suppressor Protein p53/metabolism , Acetylation , Animals , Blood Glucose/metabolism , Down-Regulation/genetics , Forkhead Box Protein O1 , Glucose-6-Phosphatase/genetics , Glucose-6-Phosphatase/metabolism , HCT116 Cells , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , Models, Biological , Phosphoenolpyruvate Carboxykinase (ATP)/genetics , Phosphoenolpyruvate Carboxykinase (ATP)/metabolism , Protein Binding , Protein Transport , Sirtuins/genetics , Transcription, Genetic
18.
Zhonghua Yi Xue Za Zhi ; 95(34): 2787-90, 2015 Sep 08.
Article in Zh | MEDLINE | ID: mdl-26711979

ABSTRACT

OBJECTIVE: To explore the possibility of using comprehensive anti-infection method during sacral neuromodulation (SNM) operation to prevent postoperative loacal incision infection. METHODS: SNM were performed for 23 patients (male 11 cases, and female 12 cases) who had intractable lower urinary tract dysfunction from January 2013 to Feburary 2015. During the treatment period (both in stage I and stage II), several steps were adopted to prevent local incision infection after operation, such as comprehensive skin disinfection, strict aseptic operating, intravenous infusion of antibiotics (cefoxitin or levofloxacin) prophylacticly at least 24 h, using sterile water to wash the incursion in operation and taking oral antibiotics anti-infection as supplemental after operation. At the meantime, microbiological examination was performed in the explanted tined leads , extension wire connection and local gluteal tissue. RESULTS: A total of 23 patients received SNM with local anesthesia, mean time of operation, hospitalization and test period were 1.5 h, 3.2 d and 37.1 d , respectively. All patients had no symptoms of clinical local infection after stage I test period and all incisions were healing with I/A standard. Eight patients were removed the inside electrodes because of poor effect at the end of test period with local anesthesia. Bacterial growth was not detected in all 8 patients of explanted tined leads and extension wire connection. And all 8 patients had their incision healed with I/A standard. Fifteen patients received implantable pulse generator (IPG) with local anesthesia. Mean time of operation was 63 min and mean time of hospitalization was 2.2 d. Among them , 10 patients' extension wire connection and loacal tissue were send to microbiological examination and no bacterial growth was found. All stage II incisions were healing with I/A standard. CONCLUSION: Perioperative comprehensive anti-infection method could prevent local incision infection after SNM.


Subject(s)
Sacrum , Electrodes, Implanted , Female , Humans , Male , Neurotransmitter Agents
19.
Invest New Drugs ; 32(1): 14-24, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23686707

ABSTRACT

Heat shock protein 90 (Hsp90) is a molecular chaperone essential for the stability and function of multiple cellular client proteins, a number of which have been implicated in the pathogenesis of breast cancer. Here we undertook a comprehensive evaluation of the activity of ganetespib, a selective Hsp90 inhibitor, in this malignancy. With low nanomolar potency, ganetespib reduced cell viability in a panel of hormone receptor-positive, HER2-overexpressing, triple-negative and inflammatory breast cancer cell lines in vitro. Ganetespib treatment induced a rapid and sustained destabilization of multiple client proteins and oncogenic signaling pathways and even brief exposure was sufficient to induce and maintain suppression of HER2 levels in cells driven by this receptor. Indeed, HER2-overexpressing BT-474 cells were comparatively more sensitive to ganetespib than the dual HER2/EGFR tyrosine kinase inhibitor lapatinib in three-dimensional culture. Ganetespib exposure caused pleiotropic effects in the inflammatory breast cancer line SUM149, including receptor tyrosine kinases, MAPK, AKT and mTOR signaling, transcription factors and proteins involved in cell cycle, stress and apoptotic regulation, as well as providing combinatorial benefit with lapatinib in these cells. This multimodal activity translated to potent antitumor efficacy in vivo, suppressing tumor growth in MCF-7 and MDA-MB-231 xenografts and inducing tumor regression in the BT-474 model. Thus, ganetespib potently inhibits Hsp90 leading to the degradation of multiple clinically-validated oncogenic client proteins in breast cancer cells, encompassing the broad spectrum of molecularly-defined subtypes. This preclinical activity profile suggests that ganetespib may offer considerable promise as a new therapeutic candidate for patients with advanced breast cancers.


Subject(s)
Breast Neoplasms/classification , Breast Neoplasms/drug therapy , HSP90 Heat-Shock Proteins/antagonists & inhibitors , Molecular Targeted Therapy , Triazoles/pharmacology , Triazoles/therapeutic use , Animals , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Breast Neoplasms/pathology , Cell Death/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Disease Models, Animal , Female , HSP90 Heat-Shock Proteins/classification , Humans , Inflammation/drug therapy , Inflammation/pathology , Mice, SCID , Protein Stability/drug effects , Receptor, ErbB-2/metabolism , Receptors, Estrogen/metabolism , Receptors, Progesterone/metabolism , Signal Transduction/drug effects , Treatment Outcome , Triple Negative Breast Neoplasms/metabolism , Triple Negative Breast Neoplasms/pathology , Xenograft Model Antitumor Assays
20.
Pharm Biol ; 52(6): 723-8, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24428850

ABSTRACT

CONTEXT: Oysters [Crassostrea plicatula Gmelin (Ostreidae)] are widely used for food in coastal areas. It is reported to have several qualities such as improving sexual and immune function. They has been approved by Chinese Ministry of Health as a functional food. OBJECTIVE: The effects of five types of oyster components (oyster meat, oyster glycogen, oyster protein, cooked liquid components, and water-insoluble components) on the swimming endurance of mice were investigated. MATERIALS AND METHODS: First, the amino acid composition and sugar content of the five oyster components were analyzed by a physicochemical test. In the in vivo test, the control group was administered distilled water, and the five intervention groups were treated with various samples for 15 consecutive days [0.8 mg protein/(g BW·d) or 0.2 mg glycogen/(g BW·d)]. The swimming time was recorded through the exhaustive swimming test. The levels of serum lactic acid, blood urea nitrogen (BUN), liver glycogen, and gastrocnemius muscle glycogen were determined. RESULTS: Oyster protein had a minimum F-value (the mole ratio of branched-chain amino acids to aromatic amino acids) (2.68), contained 1.85 mmol/mL taurine and no sugar. The components (except for oyster protein) significantly improved endurance capacity of mice and increased the liver and muscle glycogen contents (p<0.05), and reduced the lactic acid and BUN levels (p<0.05). Oyster protein had little effect. DISCUSSION AND CONCLUSION: The effects of oyster components on the swimming endurance of mice may be attributed to the high ratio of the branched-chain amino acid composition, bioactivity of taurine, and glycogen.


Subject(s)
Crassostrea , Glycogen/pharmacology , Physical Conditioning, Animal/physiology , Physical Endurance/physiology , Shellfish , Swimming/physiology , Animals , Glycogen/isolation & purification , Glycogen/metabolism , Lactic Acid/metabolism , Liver/drug effects , Liver/metabolism , Male , Mice , Muscle, Skeletal/drug effects , Muscle, Skeletal/metabolism , Physical Conditioning, Animal/methods , Physical Endurance/drug effects
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