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1.
Cureus ; 16(5): e61321, 2024 May.
Article in English | MEDLINE | ID: mdl-38947683

ABSTRACT

Carcinoid syndrome is a rare condition resulting from neuroendocrine tumors (NETs) that secrete vasoactive substances like serotonin. This report describes the case of a 61-year-old man with a history of chronic obstructive pulmonary disease (COPD) and hypertension who presented with new-onset angioedema, loss of consciousness, and a fall. He had been treated for COPD exacerbations during ER visits without improvement and was unaware of a prior mesenteric carcinoid tumor diagnosis from 2012. The next emergency evaluation revealed significant airway and facial edema necessitating intubation. Imaging and biopsy identified a well-differentiated grade 1 NET with extensive liver metastases. Laboratory tests showed elevated levels of serum serotonin, chromogranin A, and 24-hour urine 5-hydroxyindoleacetic acid (5-HIAA). Post-discharge, a PET scan confirmed metastatic lesions primarily in the liver and small bowel, with an unresectable mesenteric mass. The patient was treated with lanreotide and became symptom-free. This case underscores the need to consider carcinoid syndrome in patients with COPD presenting with unexplained respiratory symptoms, as timely diagnosis and treatment can significantly enhance patient outcomes.

2.
Adv Healthc Mater ; : e2303836, 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38507269

ABSTRACT

Chronic diabetic wounds pose significant challenges due to uncontrolled bacterial infections, prolonged inflammation, and impaired angiogenesis. The rapid advancement of photo-responsive antibacterial therapy showed promise in addressing these complex issues, particularly utilizing 2D heterojunction materials, which offer unique properties. Herein, we designed an in situ sprayed Bi/BiOCl 0D/2D heterojunction composite fibrin gel with the characteristics of rapid formation and effective near-infrared activation for the treatment of non-healing diabetes-infected wounds. The sprayed composite gel can provide protective shielding for skin tissues and promote endothelial cell proliferation, vascularization, and angiogenesis. The Bi/BiOCl 0D/2D heterojunction, with its localized surface plasmon resonance (LSPR), can overcome the wide bandgap limitation of BiOCl, enhancing the generation of local heat and reactive oxygen species under near-infrared irradiation. This facilitated bacterial elimination and reduced inflammation, supporting the accelerated healing of diabetes-infected wounds. Our study underscores the potential of LSPR-enhanced heterojunctions as advanced wound therapies for chronic diabetic wounds. This article is protected by copyright. All rights reserved.

3.
Molecules ; 28(9)2023 Apr 27.
Article in English | MEDLINE | ID: mdl-37175184

ABSTRACT

Protocatechuic acid (PCA) is a natural component with multiple biological activities. However, the underlying mechanisms of the effects of PCA on anti-ulcerative colitis (UC) are unclear. A UC mouse model was established by allowing the mice to freely drink a dextran sulfate sodium solution. The mice were administered PCA intragastrically for 7 days. Histological pathology, intestinal flora, and ferroptosis regulators were determined in vivo. Additionally, ferroptotic Caco-2 cells were modeled to investigate the role of PCA in ferroptosis. Our results showed that PCA reduced the levels of the disease activity index, inflammatory factors, and histological damage in UC mice. We also found that the regulation of intestinal flora, especially Bacteroidetes, was one of the potential mechanisms underlying the protective effects of PCA anti-UC. Moreover, PCA downregulated the level of ferroptosis in the colon tissue, as evidenced by a reduced iron overload, decreased glutathione depletion, and a lower level of malondialdehyde production compared with the model group. Similar effects of PCA on ferroptosis were observed in Erastin-treated Caco-2 cells. The results obtained using reactive oxygen species assays and the changes in mitochondrial structure observed via scanning electron microscopy also support these results. Our findings suggested that PCA protected against UC by regulating intestinal flora and ferroptosis.


Subject(s)
Colitis, Ulcerative , Colitis , Ferroptosis , Gastrointestinal Microbiome , Humans , Mice , Animals , Dextrans/pharmacology , Caco-2 Cells , Colitis, Ulcerative/chemically induced , Colon , Sulfates/pharmacology , Sodium , Dextran Sulfate/adverse effects , Disease Models, Animal , Colitis/pathology , Mice, Inbred C57BL
4.
Biosci Rep ; 43(5)2023 05 31.
Article in English | MEDLINE | ID: mdl-37022380

ABSTRACT

The ability to control stem cell function is the key to stem cell-based therapy and living tissue regeneration. In natural conditions, histone deacetylases (HDAC) are regarded as the important defining epigenetic reprogramming for stem cell differentiation. To date, human adipose-derived stem cells (hADSCs) have been widely utilised for bone tissue engineering applications. The present study aimed to examine the effect of a novel HDAC2&3-selective inhibitor, MI192, on hADSCs epigenetic reprogramming for regulating its osteogenic potential in vitro. The results confirmed that MI192 treatment reduced the hADSCs viability in a time and dose-dependent manner. The optimal concentration and pre-treatment time of MI192 for hADSCs osteogenic induction was 30 µM and 2 days representatively. A quantitative biochemical assay confirmed that the pre-treatment with MI192 (30 µM) for 2 days significantly enhanced hADSCs alkaline phosphatase (ALP) specific activity (P<0.05) compared with that of the valproic acid (VPA) pre-treatment group. Real-time PCR analysis revealed that MI192 pre-treatment up-regulated hADSCs gene expressions of osteogenic markers (e.g., Runx2, Col1, and OCN) under the osteogenic induction. DNA flow cytometric analysis indicated that two days' pre-treatment with MI192 (30 µM) resulted in G2/M arrest in hADSCs and this G2/M arrest was reversible. Our results suggest that MI192 is capable of epigenetic reprogramming of hADSCs via HDAC inhibition for controlling the cell cycle, resulting in enhancing hADSCs osteogenic differentiation, which indicates the potential of using MI192 for promoting bone tissue regeneration.


Subject(s)
Histone Deacetylase Inhibitors , Osteogenesis , Humans , Histone Deacetylase Inhibitors/pharmacology , Adipose Tissue/metabolism , Apoptosis , Cells, Cultured , Cell Line, Tumor , G2 Phase Cell Cycle Checkpoints , Cell Differentiation , Stem Cells/metabolism , Epigenesis, Genetic
5.
Medicine (Baltimore) ; 102(9): e33180, 2023 Mar 03.
Article in English | MEDLINE | ID: mdl-36862866

ABSTRACT

The significant rise of human immunodeficiency virus (HIV) epidemic among young students has become a new feature of acquired immune deficiency syndrome in China, and unprotected anal intercourse (UAI) among male students who have sex with men (SMSM) played a central role in this process. The aim of this study was to investigate the prevalence of UAI, as well as analyze the factors associated with UAI among SMSM in Qingdao, China. From May 2021 to April 2022, men who aged 15 to 30, studied in a high school or college in Qingdao and had anal sex with men in the past 6 months were recruited through snowball method relying on the nongovernmental organization. An anonymous electronic questionnaire was administrated to collect information on socio-demographic characteristics, sexual behaviors, substance use before sex, HIV prevention services and self-esteem. Univariate and multivariate logistic regressions were used to assess factors related to UAI. Among the 341 SMSM included in the study, 40.5% engaged in UAI in the past 6 months. Being migrants from other provinces [odds ratios (OR) = 2.04, 95% confidence intervals (CI): 1.10-3.78], failing to use condoms for the first anal intercourse (OR = 3.38, 95% CI: 1.85-6.18), drinking alcohol before sex (OR = 2.31, 95% CI: 1.25-4.28) and being low level self-esteem (OR = 1.77, 95% CI: 1.09-2.87) were positively associated with UAI. SMSM who had homosexual intercourse more than once a week (OR = 1.76, 95% CI: 1.03-3.00) or had multiple male sex partners (OR = 1.99, 95% CI: 1.20-3.30) were more likely to engage in UAI. Received peer education in the past 12 months (OR = 0.48, 95% CI: 0.27-0.86) was associated with lower odds of UAI. The situation of UAI among SMSM in Qingdao was a public health issue of concern. It is necessary to take targeted measures, such as focusing on first-time sex, advancing sexual health education, expanding peer education, implementing alcohol use screening and maintaining the self-esteem of SMSM, so as to reduce the occurrence of high-risk behaviors among SMSM and curb the spread of HIV on campus.


Subject(s)
Acquired Immunodeficiency Syndrome , Sexual Behavior , Male , Humans , Cross-Sectional Studies , Prevalence , China/epidemiology
6.
Article in English | MEDLINE | ID: mdl-36900791

ABSTRACT

To date, few studies have explored the role of central obesity on the association between diet quality, measured by the health eating index (HEI), inflammatory eating index (DII), and low-grade inflammation-related serum inflammatory markers. In this paper, we use the data from the 2015-2018 National Health and Nutrition Examination Survey (NHANES) to explore this. Dietary intakes were measured during two 24-h dietary recall interviews and using USDA Food Pattern Equivalence Database (FPED) dietary data. Serum inflammatory markers were obtained from NHANES Laboratory Data. Generalized structural equation models (GSEMs) were used to explore the mediating relationship. Central obesity plays a significant mediating role in the association between HEI-2015 and high-sensitivity C-reactive protein (hs-CRP), mediating 26.87% of the associations between the two; it also mediates 15.24% of the associations between DII and hs-CRP. Central obesity plays a mediating role in 13.98% of the associations between HEI-2015 and white blood cells (WBC); it also mediates 10.83% of the associations between DII and WBC. Our study suggests that central obesity plays a mediating role in the association of dietary quality with low-grade inflammation-related serum inflammatory markers (hs-CRP and WBC).


Subject(s)
C-Reactive Protein , Obesity, Abdominal , Adult , Humans , C-Reactive Protein/metabolism , Nutrition Surveys , Cross-Sectional Studies , Diet , Inflammation , Biomarkers , Obesity
7.
Nutrients ; 15(3)2023 Jan 26.
Article in English | MEDLINE | ID: mdl-36771337

ABSTRACT

In order to explore the relationship between the Healthy Eating Index (HEI-2015) and cardiovascular disease (CVD), and the mediating role of obesity and depressive symptoms, we used the data from the 2011-2018 National Health and Nutrition Examination Survey (NHANES) for further study. A total of 12,644 participants were included in the study. The HEI was derived using NHANES personal food data and USDA Food Pattern Equivalence Database (FPED) dietary data. The risk of cardiovascular disease was determined using the Framingham Heart Study's multifactorial calculation tool. The weighted multiple logistic regression model was used to explore the association between the HEI-2015 and CVD, and the generalized structural equation was used to explore the mediating effects of obesity and depression, respectively and jointly. Higher HEI-2015 scores were associated with a lower risk of CVD compared to lower quartiles. Obesity, depressive symptoms, and their chain effects all played significant mediating roles in the association between the HEI-2015 and CVD, with proportional mediations of 9.03%, 2.23% and 0.25%, respectively. Our results suggest that higher dietary quality is associated with a lower risk of CVD, mediated by obesity, depressive symptoms, and the chain effect of obesity and depressive symptoms.


Subject(s)
Cardiovascular Diseases , Depression , Humans , Nutrition Surveys , Depression/epidemiology , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/etiology , Diet/adverse effects , Obesity/epidemiology
8.
J Environ Manage ; 329: 117012, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36608618

ABSTRACT

Woody plant encroachment has been long observed in the southern Great Plains (SGP) of the United States. However, our understanding of its spatiotemporal variability, which is the basis for informed and targeted management strategy, is still poor. This study investigates the encroachment of evergreen forest, which is the most important encroachment component in the SGP. A validated evergreen forest map of the SGP (30 m resolution, for the time period 2015 to 2017) from our previous study was utilized (referred to as evergreen_base). Sample plots of evergreen forest (as of 2017) were collected across the study area, based on which a threshold of winter season (January and February) mean normalized difference vegetation index (NDVIwinter) was derived for each of the 5 sub-regions, using Landsat 7 surface reflectance data from 2015 to 2017. Then a NDVIwinter layer was created for each year within the four time periods of 1985-1989, 1995-1999, 2005-2009, and 2015-2017, with winter season surface reflectance data from Landsat 4, 5, and 7. By applying the sub-region specific NDVIwinter thresholds to the annual NDVIwinter layers and the evergreen_base, a SGP evergreen forest map was generated for each of those years. The annual evergreen forest maps within each time period were composited into one. According to the resulting four composite evergreen forest maps, mean annual encroachment rate (km2/year) was calculated at sub-region and ecoregion scales, over each of the three temporal stages 1990-1999, 2000-2009, and 2010-2017, respectively. To understand the spatiotemporal variability of the encroachment, the encroachment rate at each temporal stage was related to the corresponding initial evergreen forest area, mean annual precipitation (MAP), and mean annual burned area (MABA) through linear regression and pairwise comparison. Results suggest that most of the ecoregions have seen a slowing trend of evergreen forest encroachment since 1990. The temporal trend of encroachment rate tends to be consistent with that of MAP, but opposite to that of MABA. The spatial variability of the encroachment rate among ecoregions can be largely (>68%) explained by initial evergreen forest area but shows no significant relationship with MAP or MABA. These findings provide pertinent guidance for the combat of woody plant encroachment in the SGP under the context of climate change.


Subject(s)
Forests , Trees , Plants , Climate Change , Linear Models
9.
J Appl Toxicol ; 43(6): 772-788, 2023 06.
Article in English | MEDLINE | ID: mdl-36301730

ABSTRACT

Abnormal ovarian function is the main manifestation of female reproductive toxicity. Granulosa cells (GCs) play an important role in determining the fate of follicles and are the main effector cells of the female reproductive system. Excessive apoptosis of GCs leads to pathological folliculogenesis and further reproductive damage. However, drugs available for treatment of female reproductive toxicity are limited. Recent studies have confirmed that various natural products and bioactive ingredients of traditional Chinese medicine (TCM) can inhibit apoptosis of GCs and protect ovarian function. In this review, the mechanisms underlying the proapoptotic and antiapoptotic effects of natural products and bioactive ingredients of TCM on the proliferation, function, and apoptosis of GCs are summarized based on the findings of reports published over the past 10 years as reference for the treatment of female reproductive toxicity.


Subject(s)
Medicine, Chinese Traditional , Ovarian Follicle , Female , Humans , Granulosa Cells , Apoptosis
11.
Front Immunol ; 13: 903796, 2022.
Article in English | MEDLINE | ID: mdl-35734183

ABSTRACT

Heterogeneity of bone marrow mesenchymal stromal cells (MSCs, frequently referred to as "mesenchymal stem cells") clouds biological understanding and hampers their clinical development. In MSC cultures most commonly used in research and therapy, we have identified an MSC subtype characterized by CD317 expression (CD317pos (29.77 ± 3.00% of the total MSC population), comprising CD317dim (28.10 ± 4.60%) and CD317bright (1.67 ± 0.58%) MSCs) and a constitutive interferon signature linked to human disease. We demonstrate that CD317pos MSCs induced cutaneous tissue damage when applied a skin explant model of inflammation, whereas CD317neg MSCs had no effect. Only CD317neg MSCs were able to suppress proliferative cycles of activated human T cells in vitro, whilst CD317pos MSCs increased polarization towards pro-inflammatory Th1 cells and CD317neg cell lines did not. Using an in vivo peritonitis model, we found that CD317neg and CD317pos MSCs suppressed leukocyte recruitment but only CD317neg MSCs suppressed macrophage numbers. Using MSC-loaded scaffolds implanted subcutaneously in immunocompromised mice we were able to observe tissue generation and blood vessel formation with CD317neg MSC lines, but not CD317pos MSC lines. Our evidence is consistent with the identification of an immune stromal cell, which is likely to contribute to specific physiological and pathological functions and influence clinical outcome of therapeutic MSCs.


Subject(s)
Mesenchymal Stem Cells , Animals , Humans , Mesenchymal Stem Cells/metabolism , Mice , Signal Transduction , Stromal Cells , Th1 Cells
12.
J Funct Biomater ; 13(2)2022 Apr 10.
Article in English | MEDLINE | ID: mdl-35466223

ABSTRACT

Epigenetic approaches using the histone deacetylase 2 and 3 inhibitor-MI192 have been reported to accelerate stem cells to form mineralised tissues. Gelatine methacryloyl (GelMA) hydrogels provide a favourable microenvironment to facilitate cell delivery and support tissue formation. However, their application for bone repair is limited due to their low mechanical strength. This study aimed to investigate a GelMA hydrogel reinforced with a 3D printed scaffold to support MI192-induced human bone marrow stromal cells (hBMSCs) for bone formation. Cell culture: The GelMA (5 wt%) hydrogel supported the proliferation of MI192-pre-treated hBMSCs. MI192-pre-treated hBMSCs within the GelMA in osteogenic culture significantly increased alkaline phosphatase activity (p ≤ 0.001) compared to control. Histology: The MI192-pre-treated group enhanced osteoblast-related extracellular matrix deposition and mineralisation (p ≤ 0.001) compared to control. Mechanical testing: GelMA hydrogels reinforced with 3D printed poly(ethylene glycol)-terephthalate/poly(butylene terephthalate) (PEGT/PBT) scaffolds exhibited a 1000-fold increase in the compressive modulus compared to the GelMA alone. MI192-pre-treated hBMSCs within the GelMA-PEGT/PBT constructs significantly enhanced extracellular matrix collagen production and mineralisation compared to control (p ≤ 0.001). These findings demonstrate that the GelMA-PEGT/PBT construct provides enhanced mechanical strength and facilitates the delivery of epigenetically-activated MSCs for bone augmentation strategies.

13.
Cell Tissue Res ; 388(3): 565-581, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35362831

ABSTRACT

Epigenetics plays a critical role in regulating mesenchymal stem cells' (MSCs) fate for tissue repair and regeneration. There is increasing evidence that the inhibition of histone deacetylase (HDAC) isoform 3 can enhance MSC osteogenesis. This study investigated the potential of using a selective HDAC2 and 3 inhibitor, MI192, to promote human dental pulp stromal cells (hDPSCs) bone-like tissue formation in vitro and in vivo within porous Bombyx Mori silk scaffolds. Both 2 and 5 wt% silk scaffolds were fabricated and characterised. The 5 wt% scaffolds possess thicker internal lamellae, reduced scaffold swelling and degradation rates, whilst increased compressive modulus in comparison to the 2 wt% silk scaffold. MI192 pre-treatment of hDPSCs on 5 wt% silk scaffold significantly enhanced hDPSCs alkaline phosphatase activity (ALP). The expression of osteoblast-related genes (RUNX2, ALP, Col1a, OCN) was significantly upregulated in the MI192 pre-treated cells. Histological analysis confirmed that the MI192 pre-treated hDPSCs-silk scaffold constructs promoted bone extracellular matrix (ALP, Col1a, OCN) deposition and mineralisation compared to the untreated group. Following 6 weeks of subcutaneous implantation in nude mice, the MI192 pre-treated hDPSCs-silk scaffold constructs enhanced the vascularisation and extracellular matrix mineralisation compared to untreated control. In conclusion, these findings demonstrate the potential of using epigenetic reprogramming and silk scaffolds to promote hDPSCs bone formation efficacy, which provides evidence for clinical translation of this technology for bone augmentation.


Subject(s)
Histone Deacetylase Inhibitors , Tissue Engineering , Animals , Benzamides , Cells, Cultured , Dental Pulp/metabolism , Epigenesis, Genetic , Histone Deacetylase Inhibitors/pharmacology , Humans , Isoquinolines , Mice , Mice, Nude , Osteogenesis/genetics , Silk/pharmacology , Stromal Cells/metabolism , Tissue Scaffolds
14.
Pharm Biol ; 60(1): 501-508, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35188840

ABSTRACT

CONTEXT: The osteogenic potential of the human dental pulp stromal cells (hDPSCs) was reduced in the state of oxidative stress. Resveratrol (RSV) possesses numerous biological properties, including osteogenic potential, growth-promoting and antioxidant activities. OBJECTIVE: This study investigates the osteogenic potential of RSV by activating the Sirt1/Nrf2 pathway on oxidatively stressed hDPSCs and old mice. MATERIALS AND METHODS: The hDPSCs were subjected to reactive oxygen species (ROS) fluorescence staining, cell proliferation assay, ROS activity assay, superoxide dismutase (SOD) enzyme activity, the glutathione (GSH) concentration assay, alkaline phosphatase staining, real-time polymerase chain reaction (RT-PCR) and Sirt1 immunofluorescence labelling to assess the antioxidant stress and osteogenic ability of RSV. Forty female Kunming mice were divided into Old, Old-RSV, Young and Young-RSV groups to assess the repair of calvarial defects of 0.2 mL RSV of 20 mg/kg/d for seven days by injecting intraperitoneally at 4 weeks after surgery using micro-computed tomography, nonlinear optical microscope and immunohistochemical analysis. RESULTS: RSV abates oxidative stress by alleviating the proliferation, mitigating the ROS activity, increasing the SOD enzyme activity and ameliorating the GSH concentration (RSV IC50 in hDPSCs is 67.65 ± 9.86). The antioxidative stress and osteogenic capabilities of RSV were confirmed by the up-regulated gene expression of SOD1, xCT, RUNX2 and OCN, as well as Sirt1/Nrf2. The collagen, bone matrix formation and Sirt1 expression, are significantly increased after RSV treatment in mice. DISCUSSION AND CONCLUSIONS: For elderly or patients with oxidative stress physiological states such as hypertension, heart disease, diabetes, etc., RSV may potentially improve bone augmentation surgery in regenerative medicine.


Subject(s)
Osteogenesis/drug effects , Oxidative Stress/drug effects , Resveratrol/pharmacology , Stromal Cells/drug effects , Age Factors , Animals , Animals, Outbred Strains , Cell Proliferation/drug effects , Cells, Cultured , Dental Pulp/cytology , Female , Humans , Mice , NF-E2-Related Factor 2/metabolism , Reactive Oxygen Species/metabolism , Sirtuin 1/metabolism , Stromal Cells/cytology , Superoxide Dismutase/metabolism
15.
Acta Biomater ; 140: 190-205, 2022 03 01.
Article in English | MEDLINE | ID: mdl-34896269

ABSTRACT

The fast degradation of collagen-based membranes in the biological environment remains a critical challenge, resulting in underperforming Guided Bone Regeneration (GBR) therapy leading to compromised clinical results. Photoactive atelocollagen (AC) systems functionalised with ethylenically unsaturated monomers, such as 4-vinylbenzyl chloride (4VBC), have been shown to generate mechanically competent materials for wound healing, inflammation control and drug delivery, whereby control of the molecular architecture of the AC network is key. Building on this platform, the sequential functionalisation with 4VBC and methacrylic anhydride (MA) was hypothesised to generate UV-cured AC hydrogels with reduced swelling ratio, increased proteolytic stability and barrier functionality for GBR therapy. The sequentially functionalised atelocollagen precursor (SAP) was characterised via TNBS and ninhydrin colourimetric assays, circular dichroism and UV-curing rheometry, which confirmed nearly complete consumption of collagen's primary amino groups, preserved triple helices and fast (< 180 s) gelation kinetics, respectively. Hydrogel's swelling ratio and compression modulus were adjusted depending on the aqueous environment used for UV-curing, whilst the sequential functionalisation of AC successfully generated hydrogels with superior proteolytic stability in vitro compared to both 4VBC-functionalised control and the commercial dental membrane Bio-Gide®. These in vitro results were confirmed in vivo via both subcutaneous implantation and a proof-of-concept study in a GBR calvarial model, indicating integrity of the hydrogel and barrier defect, as well as tissue formation following 1-month implantation in rats. STATEMENT OF SIGNIFICANCE: Collagen-based membranes remain a key component in Guided Bone Regeneration (GBR) therapy, but their properties, e.g. proteolytic stability and soft tissue barrier functionality, are still far from optimal. This is largely attributed to the complex molecular configuration of collagen, which makes chemical accessibility and structure-function relations challenging. Here, we fabricated a UV-cured hydrogel network of atelocollagen, whereby triple helices were sequentially functionalised with two distinct ethylenically unsaturated monomers. The effects of the sequential functionalisation and UV-curing on the macroscopic properties, degradation behaviour and GBR capability were investigated in vitro and in vivo. The results highlight the key role of the sequential functionalisation and provide important insights for the design of future, longer-lasting resorbable membranes for GBR therapy.


Subject(s)
Guided Tissue Regeneration , Membranes, Artificial , Animals , Bone Regeneration , Collagen/pharmacology , Rats , Wound Healing
16.
Bone ; 153: 116138, 2021 12.
Article in English | MEDLINE | ID: mdl-34339909

ABSTRACT

Human bone marrow stromal cells (hBMSCs) have been extensively utilised for bone tissue engineering applications. However, they are associated with limitations that hinder their clinical utility for bone regeneration. Cell fate can be modulated via altering their epigenetic functionality. Inhibiting histone deacetylase (HDAC) enzymes have been reported to promote osteogenic differentiation, with HDAC3 activity shown to be causatively associated with osteogenesis. Therefore, this study aimed to investigate the potential of using an HDAC2 & 3 selective inhibitor - MI192 to induce epigenetic reprogramming of hBMSCs and enhance its therapeutic efficacy for bone formation. Treatment with MI192 caused a time-dose dependant reduction in hBMSCs viability. MI192 was also found to substantially alter hBMSCs epigenetic function through reduced HDAC activity and increased histone acetylation. hBMSCs were pre-treated with MI192 (50 µM) for 48 h prior to osteogenic induction. MI192 pre-treatment significantly upregulated osteoblast-related gene/protein expression (Runx2, ALP, Col1a and OCN) and enhanced alkaline phosphatase specific activity (ALPSA) (1.43-fold) (P ≤ 0.001). Moreover, MI192 substantially increased hBMSCs extracellular matrix calcium deposition (1.4-fold) (P ≤ 0.001) and mineralisation when compared to the untreated control. In 3D microtissue culture, MI192 significantly promoted hBMSCs osteoblast-related gene expression and ALPSA (> 2.41-fold) (P ≤ 0.001). Importantly, MI192 substantially enhanced extracellular matrix deposition (ALP, Col1a, OCN) and mineralisation (1.67-fold) (P ≤ 0.001) within the bioassembled-microtissue (BMT) construct. Following 8-week intraperitoneal implantation within nude mice, MI192 treated hBMSCs exhibited enhanced extracellular matrix deposition and mineralisation (2.39-fold) (P ≤ 0.001) within the BMT when compared to the untreated BMT construct. Taken together, these results demonstrate that MI192 effectively altered hBMSCs epigenetic functionality and is capable of promoting hBMSCs osteogenic differentiation in vitro and in vivo, indicating the potential of using epigenetic reprogramming to enhance the therapeutic efficacy of hBMSCs for bone augmentation strategies.


Subject(s)
Mesenchymal Stem Cells , Animals , Bone Marrow , Bone Marrow Cells , Bone Regeneration , Cell Differentiation , Cells, Cultured , Epigenesis, Genetic , Humans , Mice , Mice, Nude , Osteogenesis/genetics
17.
Int J Mol Sci ; 22(10)2021 May 14.
Article in English | MEDLINE | ID: mdl-34069280

ABSTRACT

The use of human dental pulp stromal cells (hDPSCs) has gained increasing attention as an alternative stem cell source for bone tissue engineering. The modification of the cells' epigenetics has been found to play an important role in regulating differentiation, with the inhibition of histone deacetylases 3 (HDAC3) being linked to increased osteogenic differentiation. This study aimed to induce epigenetic reprogramming using the HDAC2 and 3 selective inhibitor, MI192 to promote hDPSCs osteogenic capacity for bone regeneration. MI192 treatment caused a time-dose-dependent change in hDPSC morphology and reduction in viability. Additionally, MI192 successfully augmented hDPSC epigenetic functionality, which resulted in increased histone acetylation and cell cycle arrest at the G2/M phase. MI192 pre-treatment exhibited a dose-dependent effect on hDPSCs alkaline phosphatase activity. Quantitative PCR and In-Cell Western further demonstrated that MI192 pre-treatment significantly upregulated hDPSCs osteoblast-related gene and protein expression (alkaline phosphatase, bone morphogenic protein 2, type I collagen and osteocalcin) during osteogenic differentiation. Importantly, MI192 pre-treatment significantly increased hDPSCs extracellular matrix collagen production and mineralisation. As such, for the first time, our findings show that epigenetic reprogramming with the HDAC2 and 3 selective inhibitor MI192 accelerates the osteogenic differentiation of hDPSCs, demonstrating the considerable utility of this MSCs engineering approach for bone augmentation strategies.


Subject(s)
Benzamides/pharmacology , Dental Pulp/cytology , Histone Deacetylase Inhibitors/pharmacology , Isoquinolines/pharmacology , Osteogenesis/drug effects , Acetylation/drug effects , Alkaline Phosphatase/metabolism , Benzamides/administration & dosage , Cell Cycle/drug effects , Cell Differentiation/drug effects , Cell Survival/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Extracellular Matrix/drug effects , Extracellular Matrix/metabolism , Gene Expression Regulation/drug effects , Histone Deacetylase Inhibitors/administration & dosage , Histones/metabolism , Humans , Isoquinolines/administration & dosage , Molar, Third/cytology , Osteogenesis/physiology , Stromal Cells/metabolism
18.
Front Biosci (Landmark Ed) ; 26(12): 1737-1745, 2021 12 30.
Article in English | MEDLINE | ID: mdl-34994186

ABSTRACT

It is well-known that extracellular ATP acts as an autocrine/paracrine signal to regulate cell functions by inducing intracellular Ca2+ signalling through its cognate receptors, namely, the ligand-gated ion channel P2X receptors that mediate Ca2+ influx and/or the Gq/11-coupled P2Y receptors that link to Ca2+ release from the ER. The reduction in ER Ca2+ can trigger further extracellular Ca2+ entry by activating the store-operated Ca2+ (SOC) channel. Mesenchymal stem cells (MSC) play an important role in the homeostasis of residing tissues and have promising applications in regenerative medicines. MSC can release ATP spontaneously or in response to diverse stimuli, and express multiple P2X and Gq/11-coupled P2Y receptors that participate in ATP-induced Ca2+ signalling and regulate cell function. There is increasing evidence to show the contribution of the SOC channel in ATP-induced Ca2+ signalling in MSC. In this mini-review, we discuss the current understanding of the expression of the SOC channel in MSC and its potential role in mediating ATP-induced Ca2+ signalling and regulation of MSC differentiation, proliferation and migration.


Subject(s)
Mesenchymal Stem Cells , Receptors, Purinergic P2 , Adenosine Triphosphate , Calcium/metabolism , Calcium Signaling , Mesenchymal Stem Cells/metabolism , Receptors, Purinergic P2/metabolism , Signal Transduction
19.
Mitochondrial DNA B Resour ; 5(1): 1021-1022, 2020 Feb 03.
Article in English | MEDLINE | ID: mdl-33366856

ABSTRACT

In this study, the complete mitogenome of an entomopathogenic fungus Akanthomyces lecanii is assembled and annotated. This circular mitogenome is 24,643 bp in length and consists of 2 rRNA genes (rnl and rns), 26 tRNA genes and 14 standard protein-coding genes of the oxidative phosphorylation system. Only one intron (group IA) is identified, which invades rnl and carries an ORF coding for ribosomal protein S3. Phylogenetic analysis based on concatenated mitochondrial nucleotide sequences confirms A. lecanii in Cordycipitaceae, and A. lecanii clusters together with Akanthomyces muscarius.

20.
Int J Biol Macromol ; 165(Pt B): 2022-2029, 2020 Dec 15.
Article in English | MEDLINE | ID: mdl-33080264

ABSTRACT

Regulating the activity of matrix metalloproteinases (MMPs) is a potential strategy for osteoarthritis (OA) therapy, although delivering this effect in a spatially and temporally localised fashion remains a challenge. Here, we report an injectable and self-healing hydrogel enabling factor-free MMP regulation and biomechanical competence in situ. The hydrogel is realised within 1 min upon room temperature coordination between hyaluronic acid (HA) and a cell-friendly iron-glutathione complex in aqueous environment. The resultant gel displayed up to 300% in shear strain and tolerance towards ATDC 5 chondrocytes, in line with the elasticity and biocompatibility requirements for connective tissue application. Significantly enhanced inhibition of MMP-13 activity was achieved after 12 h in vitro, compared with a commercial HA injection (OSTENIL® PLUS). Noteworthy, 24-hour incubation of a clinical synovial fluid sample collected from a late-stage OA patient with the reported hydrogel was still shown to downregulate synovial fluid MMP activity (100.0 ± 17.6% ➔ 81.0 ± 7.5%), with at least comparable extent to the case of the OSTENIL® PLUS-treated SF group (100.0 ± 17.6% ➔ 92.3 ± 27.3%). These results therefore open up new possibilities in the use of HA as both mechanically-competent hydrogel as well as a mediator of MMP regulation for OA therapy.


Subject(s)
Gels/chemistry , Hyaluronic Acid/pharmacology , Injections , Iron/chemistry , Matrix Metalloproteinase Inhibitors/pharmacology , Matrix Metalloproteinases/metabolism , Cell Line , Cell Survival/drug effects , Elastic Modulus , Glutathione/chemistry , Humans , Spectroscopy, Mossbauer , Synovial Fluid/enzymology , Time Factors , Viscosity
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