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1.
IUBMB Life ; 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39139071

ABSTRACT

Senescent cells are typically characterized by a stable proliferation arrested in dividing cells accompanied with a senescence-associated secretory phenotype (SASP). Skin cellular senescence is the primary cause of skin aging, whereas the lack of identified skin senescence markers limits our understanding of the mechanisms involved in skin aging. Recent studies have revealed that intracellular calcium signaling has emerged as a key player in regulating cellular senescence and aging. However, the implication and roles of calcium signaling in skin keratinocyte senescence remain only partially understood. In this study, we developed a model for skin keratinocyte senescence using ionizing radiation (I/R) stimulation and found that the calcium-associated gene transglutaminase 2 (TGM2) was significantly induced compared with normal control. Interestingly, inhibition of TGM2 was found to delay skin keratinocyte senescence by suppressing I/R-promoted intracellular calcium signaling, accumulation of reactive oxygen species (ROS), DNA damage, as well as NF-κB-mediated SASP secretion. Taken together, our findings demonstrate that inhibition of TGM2 contributes to bypassing I/R-induced skin keratinocyte senescence and sheds light on novel strategies against skin stresses caused by I/R.

2.
Phys Chem Chem Phys ; 26(32): 21801-21809, 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39101765

ABSTRACT

Lead-free halide perovskites have recently garnered significant attention due to their rich structural diversity and exceptionally ultralow lattice thermal conductivity (κL). Here, we employ first-principles calculations in conjunction with self-consistent phonon theory and Boltzmann transport equations to investigate the crystal structure, electronic structure, mechanical properties, and κLs of two typical vacancy-ordered halide perovskites, denoted with the general formula Cs3Bi2X9 (X = Br, I). Ultralow κLs of 0.401 and 0.262 W mK-1 at 300 K are predicted for Cs3Bi2Br9 and Cs3Bi2I9, respectively. Our findings reveal that the ultralow κLs are mainly associated with the Cs rattling-like motion, vibrations of halide polyhedral frameworks, and strong scattering in the acoustic and low-frequency optical phonon branches. The structural analysis indicates that these phonon dynamic properties are closely relevant to the bonding hierarchy. The presence of the extended Bi-X antibonding states at the valence band maximum contributes to the soft elastic lattice and low phonon group velocities. Compared to Cs3Bi2Br9, the face-sharing feature and weaker bond strength in Cs3Bi2I9 lead to a softer elasticity modulus and stronger anharmonicity. Additionally, we demonstrate the presence of wave-like κC in Cs3Bi2X9 by evaluating the coherent contribution. Our work provides the physical microscopic mechanisms of the wave-like κC in two typical lead-free halide perovskites, which are beneficial to designing intrinsic materials with the feature of ultralow κL.

3.
Int J Geriatr Psychiatry ; 39(7): e6117, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38925887

ABSTRACT

OBJECTIVES: This study aimed to evaluate the efficacy of different repetitive transcranial magnetic stimulation (rTMS) modes in stroke patients with cognitive impairment, and to rank the best option according to the outcome measures. METHODS: Literature was searched in PubMed, Cochrane Library, Web of Science, Embase, SinoMed, China National Knowledge Infrastructure, Wanfang Database, and VIP Database, from database inception to September 2023. We included randomized controlled trials (RCTs) investigating the efficacy of all rTMS modes for post-stroke cognitive impairment. The selected studies assessed at least one of the following outcome measures: Montreal Cognitive Assessment (MoCA), Mini-Mental State Examination (MMSE), P300 latency and amplitude, and modified Barthel Index (MBI) or BI. Two researchers independently conducted data extraction. Quality assessment was performed using RevMan 5.3 software based on the Cochrane Collaboration's tool, and statistical analysis was conducted by GeMTC 0.14.3 software and Stata 17.0 software. RESULTS: The network meta-analysis included 74 RCTs with a total of 5478 patients. The best probability ranking indicated that intermittent theta burst stimulation (iTBS) was the most effective in enhancing MoCA, MMSE and MBI scores (85%, 54%, 42%, respectively), followed by 10 Hz rTMS (79%, 50%, 39%, respectively), for P300 amplitude, ≤1 Hz rTMS was ranked first (52%). CONCLUSIONS: The current limited evidence suggests that iTBS may be the optimal approach for improving cognitive and daily life abilities of stroke patients, followed by 10 Hz rTMS, ≤1 Hz rTMS may be the preferred option for enhancing P300 amplitude. TRAIL REGISTRATION: PROSPERO 2023 CRD42023424771 available from: https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=424771.


Subject(s)
Cognitive Dysfunction , Network Meta-Analysis , Stroke , Transcranial Magnetic Stimulation , Humans , Cognitive Dysfunction/therapy , Cognitive Dysfunction/etiology , Cognitive Dysfunction/physiopathology , Stroke/complications , Stroke/physiopathology , Transcranial Magnetic Stimulation/methods , Stroke Rehabilitation/methods , Randomized Controlled Trials as Topic , Mental Status and Dementia Tests
4.
J Shoulder Elbow Surg ; 33(8): 1685-1693, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38609005

ABSTRACT

BACKGROUND: Coronal shear fractures of the distal humerus are not only rare and prone to misdiagnosis, but their surgical treatment can be challenging. We aimed to investigate the feasibility of exposing distal humeral coronal shear fractures with a combined lateral approach that preserves the extensors and lateral ulnar collateral ligament (LUCL) and to analyze the clinical efficacy of open reduction and internal fixation in the treatment of these injuries. METHODS: We included 45 patients who sustained coronal shear fractures of the distal humerus with the lateral epicondyle intact and were treated with open reduction and internal fixation from January 2013 to August 2020. The fractures were exposed by the lateral combined approach in which the tendons involving the common extensor, the extensor carpi ulnaris, and the LUCL were preserved. Two observation windows were formed anterior to and posterior to these tendons and the LUCL was used to achieve fracture reduction. Countersunk screws, with or without a plate placed on the posterior lateral condyle, were used to fix the fragments. The functional outcomes of these patients were reviewed and assessed with physical and radiographic examinations, range of motion measurements, and self-evaluation Mayo Elbow Performance Index and the Disabilities of the Arm, Shoulder, and Hand scores. RESULTS: In total, 40 patients were followed up with for over 1 year and were included in the final analysis. The mean follow-up duration was 42 ± 30 months (range, 12-107 months). The patients' mean age was 42 years (range, 14-74 years). According to the Dubberley Classification, there were 15 type I, 17 type II, and 8 type III fractures. At the final follow-up, the mean flexion-extension arc was 131° (range, 65-150) and mean pronation and supination was 73° (range, 45-80) and 71° (range, 40-80), respectively. The mean Mayo Elbow Performance Index score was 88 (range, 61-97) points; the results were excellent in 21, good in 13, fair in 4, and poor in 2 patients. The mean Disabilities of the Arm, Shoulder, and Hand score was 11 (range, 0-42) points. Neither functional score nor range of movement was associated with age, sex, fracture type, injury type, or surgical timing. CONCLUSION: Reduction and stable fixation with internal fixation for coronal shear fractures of the distal humerus can be achieved by the lateral combined approach. Early functional mobilization allows for satisfactory restoration of elbow function.


Subject(s)
Fracture Fixation, Internal , Humeral Fractures , Humans , Male , Female , Fracture Fixation, Internal/methods , Humeral Fractures/surgery , Middle Aged , Adult , Range of Motion, Articular , Retrospective Studies , Aged , Elbow Joint/surgery , Elbow Joint/physiopathology , Treatment Outcome , Young Adult , Open Fracture Reduction/methods
5.
Molecules ; 29(12)2024 Jun 08.
Article in English | MEDLINE | ID: mdl-38930799

ABSTRACT

Four new diterpenoids, isodosins A-D (1-4), together with nine known compounds (5-13) were isolated and identified from the aerial parts of Isodon serra (Maxim.) Hara. The structures of the new diterpenoids were elucidated based on the analysis of HR-ESI-MS data, 1D/2D-NMR-spectroscopic data, and electronic circular dichroism (ECD) calculations. Cytotoxicities of compounds 2, 3, 5, 6, and 9 against the HepG2 and H1975 cell lines were evaluated with the MTT assay. As a result, compounds 2, 3, and 6 revealed higher levels of cytotoxicity against HepG2 cells than against H1975 cells. Moreover, compund 6 demonstrated the most efficacy in inhibiting the proliferation of HepG2 cells, with an IC50 value of 41.13 ± 3.49 µM. This effect was achieved by inducing apoptosis in a dose-dependent manner. Furthermore, the relationships between the structures and activities of these compounds are briefly discussed.


Subject(s)
Antineoplastic Agents, Phytogenic , Apoptosis , Diterpenes , Isodon , Plant Components, Aerial , Humans , Diterpenes/chemistry , Diterpenes/pharmacology , Diterpenes/isolation & purification , Isodon/chemistry , Plant Components, Aerial/chemistry , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/isolation & purification , Apoptosis/drug effects , Hep G2 Cells , Molecular Structure , Cell Line, Tumor , Cell Proliferation/drug effects , Plant Extracts/chemistry , Plant Extracts/pharmacology , Structure-Activity Relationship , Cell Survival/drug effects , Drug Screening Assays, Antitumor
6.
Int J Neurosci ; : 1-4, 2023 Mar 30.
Article in English | MEDLINE | ID: mdl-36994695

ABSTRACT

INTRODUCTION: Chronic subdural hematoma (CSDH) often occurs 3 weeks to 3 months after brain injury, which is mainly caused by bleeding of the bridging vein. For patients with ventriculoperitoneal (V-P) shunt, excessive drainage can also cause CSDH. We present a rare case of CSDH caused by shunt valve breakdown in brain injury. CASE REPORT: We report a 68-year-old man with V-P shunt for 8 years. He presented with bilateral CSDH with disappearance of lateral ventricles nearly 1 month after a brain injury caused by being hit with a stick. After burr hole drainage (BHD), the patient's symptoms improved and lateral ventricles reappeared, but disappeared rapidly with CSDH recurrence within a short time. We considered the cause to be medium pressure shunt valve breakdown caused by hitting with a stick, which was confirmed by the engineer's test after the operation and excessive drainage of cerebrospinal fluid. BHD replaced the adjustable pressure shunt valve, and the patient recovered. CONCLUSION: V-P shunt is a common operation in neurosurgery, and postoperative shunt valve breakdown may lead to poor outcome. We report a rare case of CSDH caused by shunt valve breakdown due to excessive external forces, suggesting that patients after V-P shunt should pay attention to the protection of the shunt valve.

7.
Hepatology ; 74(1): 264-280, 2021 07.
Article in English | MEDLINE | ID: mdl-33462832

ABSTRACT

BACKGROUND AND AIMS: Mutational signature analyses are an effective tool in identifying cancer etiology. Humans are frequently exposed to pyrrolizidine alkaloids (PAs), the most common carcinogenic phytotoxins widely distributed in herbal remedies and foods. However, due to the lack of human epidemiological data, PAs are classified as group II hepatocarcinogens by the World Health Organization. This study identified a PA mutational signature as the biomarker to investigate the association of PA exposure with human liver cancer. APPROACH AND RESULTS: Pyrrole-protein adducts (PPAs), the PA exposure biomarker, were measured and found in 32% of surgically resected specimens from 34 patients with liver cancer in Hong Kong. Next, we delineated the mode of mutagenic and tumorigenic actions of retrorsine, a representative PA, in mice and human hepatocytes (HepaRG). Retrorsine induced DNA adduction, DNA damage, and activation of tumorigenic hepatic progenitor cells, which initiated hepatocarcinogenesis. PA mutational signature, as the unique molecular fingerprint of PA-induced mutation, was derived from exome mutations in retrorsine-exposed mice and HepaRG cells. Notably, PA mutational signature was validated in genomes of patients with PPA-positive liver cancer but not patients with PPA-negative liver cancer, confirming the specificity of this biomarker in revealing PA-associated liver cancers. Furthermore, we examined the established PA mutational signature in 1,513 liver cancer genomes and found that PA-associated liver cancers were potentially prevalent in Asia (Mainland China [48%], Hong Kong [44%], Japan [22%], South Korea [6%], Southeast Asia [25%]) but minor in Western countries (North America [3%] and Europe [5%]). CONCLUSIONS: This study provides a clinical indication of PA-associated liver cancer. We discovered an unexpectedly extensive implication of PA exposure in patients with liver cancer, laying the scientific basis for precautionary approaches and prevention of PA-associated human liver cancers.


Subject(s)
Carcinogenesis/chemically induced , DNA Damage/drug effects , Liver Neoplasms, Experimental/chemically induced , Liver Neoplasms/chemically induced , Pyrrolizidine Alkaloids/adverse effects , Animals , Carcinogenesis/genetics , Cell Line, Tumor , DNA Mutational Analysis , Female , Humans , Liver/drug effects , Liver/pathology , Liver Neoplasms/genetics , Liver Neoplasms/pathology , Liver Neoplasms, Experimental/genetics , Liver Neoplasms, Experimental/pathology , Male , Mice , Exome Sequencing
8.
Phys Chem Chem Phys ; 24(12): 7303-7310, 2022 Mar 23.
Article in English | MEDLINE | ID: mdl-35262117

ABSTRACT

Combining density functional theory (DFT) and semi-classic Boltzmann transport theory, we report the thermoelectric (TE) performance of a family of two-dimensional (2D) group IB-selenides XSe (X = Cu, Ag, Au). The results show that these monolayers exhibit small and anisotropic phonon velocities (0.98-3.84 km s-1), large Grüneisen parameters (up to 100), and drastic phonon scattering between the optical and acoustic phonons. These intrinsic properties originate from strong phonon anharmonicity and suppress the heat transport capacity, resulting in low lattice thermal conductivities (12.54 and 1.22 W m-1 K-1) along the x- and y-directions for a CuSe monolayer. Among our studied monolayers, the 2D CuSe monolayer possesses the most remarkable TE performance with ultrahigh ZT (3.26) for n-type doping along the y-direction at 300 K. CuSe monolayer can achieve higher thermoelectric conversion efficiency at a lower synthetic preparation cost than the expensive AgSe and AuSe monolayers, and our work provides a theoretical basis for paving the way for further experimental studies.

9.
Phys Chem Chem Phys ; 24(35): 21261-21269, 2022 Sep 14.
Article in English | MEDLINE | ID: mdl-36040434

ABSTRACT

In layered materials with the stacking axis perpendicular to the basal plane, anharmonicity strongly affects phonon propagation due to weak interlayer coupling, which is helpful to reduce the lattice thermal conductivity and improve the thermoelectric (TE) performance significantly. By combining first-principles calculations and the Boltzmann transport equation, we systematically analyzed and evaluated the lattice thermal conductivity and TE properties of LaMOCh (M = Cu, Ag; Ch = S, Se). The results indicate that these layered materials exhibit ultralow lattice thermal conductivities of 0.24-0.37 W m-1 K-1 along the interlayer direction at room temperature. The low lattice thermal conductivities have been analyzed from some inherent phonon properties, such as low acoustic phonon group velocity, large Grüneisen parameters, and a short phonon relaxation time. Originating from their natural layered crystal structure, the thermal and electronic transports (i.e., thermal conductivity, Seebeck coefficient, and electrical conductivity) are both highly anisotropic between their intralayer and interlayer directions. Finally, we obtained ZT values of 1.17 and 1.26 at 900 K along the interlayer direction for n-type LaCuOSe and LaAgOSe, respectively. Generally, LaMOSe exhibit larger anisotropy than LaMOS, in both n- and p-types of doping. Our findings of low thermal conductivities and large anisotropic TE performances of these layered systems should stimulate much attention in BiCuOSe and alike layered TE families.

10.
Arch Toxicol ; 96(2): 639-651, 2022 02.
Article in English | MEDLINE | ID: mdl-34792613

ABSTRACT

Pyrrolizidine alkaloids (PAs) are phytotoxins widely present in various natural products and foodstuffs. The present study aims to investigate the effects of fasting on PA-induced hepatotoxicity and the underlying biochemical mechanisms. The results of hepatotoxic study showed that 15-h overnight fasting significantly exacerbated the hepatotoxicity of retrorsine (RTS, a representative toxic PA) in fasted rats compared to fed rats, as indicated by remarkably elevated plasma ALT and bilirubin levels and obvious liver histological changes. Further toxicokinetic studies revealed that fasting significantly enhanced cytochromes P450 enzymes (CYPs)-mediated metabolic activation of RTS leading to increased formation of pyrrole-protein adducts and thus decreased the in vivo exposure and excretion of both parent RTS and its N-oxide metabolite. Metabolic studies demonstrated that fasting induced enzyme activities of CYP1A2, CYP2B6 and CYP2E1 that participated in catalyzing RTS to its reactive pyrrolic metabolites. Moreover, fasting also dramatically decreased hepatic glutathione (GSH) content, which restricted the detoxification of GSH by neutralizing the reactive pyrrolic metabolite of RTS, further contributing to the enhanced hepatotoxicity. The present findings may have an impact on future PA toxicity tests with different dietary styles and/or risk assessment of metabolite-mediated toxins by considering the profound effects of fasting.


Subject(s)
Chemical and Drug Induced Liver Injury/etiology , Fasting , Pyrrolizidine Alkaloids/toxicity , Alanine Transaminase/blood , Animals , Bilirubin/blood , Cytochrome P-450 Enzyme System/metabolism , Glutathione/metabolism , Liver/drug effects , Liver/pathology , Male , Pyrrolizidine Alkaloids/metabolism , Rats , Rats, Sprague-Dawley
11.
Genomics ; 113(3): 867-873, 2021 05.
Article in English | MEDLINE | ID: mdl-33545268

ABSTRACT

The efficacy of susceptible variants derived from genome-wide association studies (GWAs) optimizing discriminatory accuracy of colorectal cancer (CRC) in Chinese remains unclear. In the present validation study, we assessed 75 recently identified variants from GWAs. A risk predictive model combining 19 variants using the least absolute shrinkage and selection operator (LASSO) statistics offered certain clinical advantages. This model demonstrated an area under the receiver operating characteristic (AUC) of 0.61 during training analysis and yielded robust AUCs from 0.59 to 0.61 during validation analysis in three independent centers. The individuals carrying the highest quartile of risk score revealed over 2-fold risks of CRC (ranging from 2.12 to 2.90) compared with those who presented the lowest quartile of risk score. This genetic model offered the possibility of partitioning risk within the average risk population, which might serve as a first step toward developing individualized CRC prevention strategies in China.


Subject(s)
Colorectal Neoplasms , Genome-Wide Association Study , Asian People/genetics , Colorectal Neoplasms/genetics , Genetic Predisposition to Disease , Humans , Polymorphism, Single Nucleotide , ROC Curve , Risk Factors
12.
BMC Nurs ; 21(1): 67, 2022 Mar 24.
Article in English | MEDLINE | ID: mdl-35331202

ABSTRACT

BACKGROUND: Nursing and medical students are suffering from high rates of depressive symptoms. Mental health benefits students' learning, growth and professional development. Exploring psychological resources to prevent depression is emphasized recently, and self-compassion is shown to be inversely associated with depressive symptoms. However, the mechanism through which self-compassion contributes to decreased depressive symptoms is limited. Therefore, this study aimed to explore and examine a model detailing the potential paths between self-compassion and depressive symptoms. METHODS: A cross-sectional study was conducted and convenient sampling was used. Among the 1800 nursing and medical students targeted from two universities in East and North China, 1341 completed the questionnaires, and 1127 valid questionnaires were analyzed comprising 566 and 561 from medical and nursing students, respectively. Data in May 2020 and July 2020 were collected through Patient Health Questionnaire, self-compassion scale, resilience scale, Life Orientation Test and Perceived Stress Scale. Then, path model analysis was conducted to analyze the data. RESULTS: Finally, this study included 1125 valid questionnaires after excluding two extremes of study variables. Participants consisted of 50.2% medical students and 49.8% nursing students. The model showed an acceptable fit to the data. After controlling for the demographics, self-compassion was directly and indirectly associated with decreased depressive symptoms by increasing resilience and optimism and reducing perceived stress among nursing and medical students. Resilience and optimism were directly and indirectly associated with decreased depressive symptoms by reducing perceived stress among nursing students and indirectly associated with decreased depressive symptoms among medical students. CONCLUSIONS: The study provides evidence that self-compassion significantly influences the decrease in depressive symptoms by increasing resilience and optimism and reducing perceived stress. These findings suggested that programs enhancing students' self-compassion, resilience, and optimism simultaneously can help decrease depressive symptoms and improve mental health in education and healthcare institutes. These findings may facilitate the designing of educational programs for preventing depressive symptoms and promoting mental health among nursing and medical students.

13.
Phys Chem Chem Phys ; 23(11): 6388-6396, 2021 Mar 21.
Article in English | MEDLINE | ID: mdl-33704316

ABSTRACT

Through first-principles calculations, we report the thermoelectric properties of two-dimensional (2D) hexagonal group-IV tellurides XTe (X = Ge, Sn and Pb), with quadruple layers (QL) in the Te-X-X-Te stacking sequence, as promising candidates for mid-temperature thermoelectric (TE) materials. The results show that 2D PbTe exhibits a high Seebeck coefficient (∼1996 µV K-1) and a high power factor (6.10 × 1011 W K-2 m-1 s-1) at 700 K. The lattice thermal conductivities of QL GeTe, SnTe and PbTe are calculated to be 2.29, 0.29 and 0.15 W m-1 K-1 at 700 K, respectively. Using our calculated transport parameters, large values of the thermoelectric figure of merit (ZT) of 0.67, 1.90, and 2.44 can be obtained at 700 K under n-type doping for 2D GeTe, SnTe, and PbTe, respectively. Among the three compounds, 2D PbTe exhibits low average values of sound velocity (0.42 km s-1), large Grüneisen parameters (∼2.03), and strong phonon scattering. Thus, 2D PbTe shows remarkable mid-temperature TE performance with a high ZT value under both p-type (2.39) and n-type (2.44) doping. The present results may motivate further experimental efforts to verify our predictions.

14.
Acta Pharmacol Sin ; 42(8): 1212-1222, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33154553

ABSTRACT

Herbs and dietary supplement-induced liver injury (HILI) is the leading cause of drug-induced liver injury in China. Among different hepatotoxic herbs, the pyrrolizidine alkaloid (PA)-producing herb Gynura japonica contributes significantly to HILI by inducing hepatic sinusoidal obstruction syndrome (HSOS), a liver disorder characterized by hepatomegaly, hyperbilirubinemia, and ascites. In China, G. japonica has been used as one of the plant species for Tu-San-Qi and is often misused with non-PA-producing Tu-San-Qi (Sedum aizoon) or even San-Qi (Panax notoginseng) for self-medication. It has been reported that over 50% of HSOS cases are caused by the intake of PA-producing G. japonica. In this review, we provide comprehensive information to distinguish these Tu-San-Qi-related herbal plant species in terms of plant/medicinal part morphologies, medicinal indications, and chemical profiles. Approximately 2156 Tu-San-Qi-associated HSOS cases reported in China from 1980 to 2019 are systematically reviewed in terms of their clinical manifestation, diagnostic workups, therapeutic interventions, and outcomes. In addition, based on the application of our developed mechanism-based biomarker of PA exposure, our clinical findings on the definitive diagnosis of 58 PA-producing Tu-San-Qi-induced HSOS patients are also elaborated. Therefore, this review article provides the first comprehensive report on 2214 PA-producing Tu-San-Qi (G. japonica)-induced HSOS cases in China, and the information presented will improve public awareness of the significant incidence of PA-producing Tu-San-Qi (G. japonica)-induced HSOS and facilitate future prevention and better clinical management of this severe HILI.


Subject(s)
Chemical and Drug Induced Liver Injury, Chronic/drug therapy , Drugs, Chinese Herbal/poisoning , Pyrrolizidine Alkaloids/poisoning , Asteraceae/chemistry , Biomarkers/blood , Chemical and Drug Induced Liver Injury, Chronic/blood , Chemical and Drug Induced Liver Injury, Chronic/diagnosis , China , Drugs, Chinese Herbal/chemistry , Drugs, Chinese Herbal/metabolism , Humans , Panax notoginseng/chemistry , Pyrrolizidine Alkaloids/chemistry , Pyrrolizidine Alkaloids/metabolism , Sedum/chemistry
15.
Arch Toxicol ; 95(6): 1917-1942, 2021 06.
Article in English | MEDLINE | ID: mdl-34003343

ABSTRACT

Pyrrolizidine alkaloids (PAs) and PA N-oxides are common phytotoxins produced by over 6000 plant species. Humans are frequently exposed to PAs via ingestion of PA-containing herbal products or PA-contaminated foods. PAs require metabolic activation to form pyrrole-protein adducts and pyrrole-DNA adducts which lead to cytotoxicity and genotoxicity. Individual PAs differ in their metabolic activation patterns, which may cause significant difference in toxic potency of different PAs. This review discusses the current knowledge and recent advances of metabolic pathways of different PAs, especially the metabolic activation and metabolism-mediated cytotoxicity and genotoxicity, and the risk evaluation methods of PA exposure. In addition, this review provides perspectives of precision toxicity assessment strategies and biomarker development for the risk control and translational investigations of human intoxication by PAs.


Subject(s)
DNA Adducts/toxicity , DNA Damage/drug effects , Pyrrolizidine Alkaloids/toxicity , Animals , Biomarkers/metabolism , DNA Adducts/chemistry , Humans , Mutagens/metabolism , Mutagens/toxicity , Pyrrolizidine Alkaloids/metabolism , Risk Assessment/methods
16.
Arch Toxicol ; 95(1): 103-116, 2021 01.
Article in English | MEDLINE | ID: mdl-33033841

ABSTRACT

Pyrrolizidine alkaloids (PAs) are common phytotoxins with both hepatotoxicity and pneumotoxicity. Hepatic cytochrome P450 enzymes are known to bioactivate PAs into reactive metabolites, which can interact with proteins to form pyrrole-protein adducts and cause intrahepatic cytotoxicity. However, the metabolic and initiation biochemical mechanisms underlying PA-induced pneumotoxicity remain unclear. To investigate the in vivo metabolism basis for PA-induced lung injury, this study used mice with conditional deletion of the cytochrome P450 reductase (Cpr) gene and resultant tissue-selective ablation of microsomal P450 enzyme activities. After oral exposure to monocrotaline (MCT), a pneumotoxic PA widely used to establish animal lung injury models, liver-specific Cpr-null (LCN) mice, but not extrahepatic Cpr-low (xh-CL) mice, had significantly lower level of pyrrole-protein adducts in the serum, liver and lungs compared with wild-type (WT) mice. While MCT-exposed LCN mice had significantly higher blood concentration of intact MCT, compared to MCT-exposed WT or xh-CL mice. Consistent with the MCT in vivo bioactivation data, MCT-induced lung injury, represented by vasculature damage, in WT and xh-CL mice but not LCN mice. Furthermore, reactive metabolites of MCT were confirmed to exist in the blood efflux from the hepatic veins of MCT-exposed rats. Our results provide the first mode-of-action evidence that hepatic P450s are essential for the bioactivation of MCT, and blood circulating reactive metabolites of MCT to the lung causes pneumotoxicity. Collectively, this study presents the scientific basis for the application of MCT in animal lung injury models, and more importantly, warrants public awareness and further investigations of lung diseases associated with exposure to not only MCT but also different PAs.


Subject(s)
Cytochrome P-450 Enzyme System/metabolism , Liver/enzymology , Lung Injury/chemically induced , Lung/drug effects , Monocrotaline/toxicity , NADPH-Ferrihemoprotein Reductase/metabolism , Activation, Metabolic , Animals , Isoenzymes , Lung/metabolism , Lung/pathology , Lung Injury/blood , Lung Injury/enzymology , Lung Injury/pathology , Male , Mice, Inbred C57BL , Mice, Knockout , Monocrotaline/blood , NADPH-Ferrihemoprotein Reductase/genetics , Protein Binding , Rats, Sprague-Dawley , Toxicokinetics
17.
Arch Toxicol ; 95(2): 759-765, 2021 02.
Article in English | MEDLINE | ID: mdl-33210216

ABSTRACT

Pyrrolizidine alkaloids (PAs) are naturally occurring hepatotoxins widely present in hundreds of plant species and also known to contaminate many foodstuffs, such as grain, honey, and tea. The formation of pyrrole-protein adducts via metabolic activation of PAs has been suggested as a primary trigger initiating hepatotoxicity. The present study for the first time tested the suitability of pyrrole-hemoglobin adducts as a novel and specific biomarker of PA exposure in humans. The level and elimination kinetics of pyrrole-hemoglobin adducts were systematically investigated in the blood samples of 43 PA-induced liver injury (PA-ILI) patients. The results revealed significantly higher concentrations (84.50 ± 78.38 nM) and longer persistence (~ 4 months) of pyrrole-hemoglobin adducts than that (concentration: 9.53 ± 10.72 nM; persistence: ~ 2 months) of pyrrole-plasma protein adducts, our previously developed PA exposure biomarker. Our findings confirmed that pyrrole-hemoglobin adducts with higher level and longer persistence should serve as a more applicable PA exposure biomarker for future clinical diagnosis of PA-ILI in drug/herb-induced liver injury patients.


Subject(s)
Blood Proteins/metabolism , Chemical and Drug Induced Liver Injury/metabolism , Hemoglobins/metabolism , Pyrroles/metabolism , Pyrrolizidine Alkaloids/metabolism , Pyrrolizidine Alkaloids/toxicity , Activation, Metabolic , Adult , Aged , Aged, 80 and over , Biomarkers/metabolism , Chemical and Drug Induced Liver Injury/diagnosis , Female , Humans , Kinetics , Liver/drug effects , Liver/metabolism , Male , Middle Aged
18.
Arch Toxicol ; 95(10): 3191-3204, 2021 10.
Article in English | MEDLINE | ID: mdl-34390356

ABSTRACT

Pyrrolizidine alkaloids (PAs) have been found in over 6000 plants worldwide and represent the most common hepatotoxic phytotoxins. Currently, a definitive diagnostic method for PA-induced liver injury (PA-ILI) is lacking. In the present study, using a newly developed analytical method, we identified four pyrrole-amino acid adducts (PAAAs), namely pyrrole-7-cysteine, pyrrole-9-cysteine, pyrrole-9-histidine, and pyrrole-7-acetylcysteine, which are generated from reactive pyrrolic metabolites of PAs, in the urine of PA-treated male Sprague Dawley rats and PA-ILI patients. The elimination profiles, abundance, and persistence of PAAAs were systematically investigated first in PA-treated rat models via oral administration of retrorsine at a single dose of 40 mg/kg and multiple doses of 5 mg/kg/day for 14 consecutive days, confirming that these urinary excreted PAAAs were derived specifically from PA exposure. Moreover, we determined that these PAAAs were detected in ~ 82% (129/158) of urine samples collected from ~ 91% (58/64) of PA-ILI patients with pyrrole-7-cysteine and pyrrole-9-histidine detectable in urine samples collected at 3 months or longer times after hospital admission, indicating adequate persistence time for use as a clinical test. As direct evidence of PA exposure, we propose that PAAAs can be used as a biomarker of PA exposure and the measurement of urinary PAAAs could be used as a non-invasive test assisting the definitive diagnosis of PA-ILI in patients.


Subject(s)
Amino Acids/metabolism , Chemical and Drug Induced Liver Injury/etiology , Pyrroles/metabolism , Pyrrolizidine Alkaloids/toxicity , Adult , Aged , Aged, 80 and over , Animals , Biomarkers/metabolism , Chemical and Drug Induced Liver Injury/diagnosis , Female , Humans , Male , Middle Aged , Pyrrolizidine Alkaloids/administration & dosage , Pyrrolizidine Alkaloids/pharmacokinetics , Rats , Rats, Sprague-Dawley , Time Factors
19.
Med Sci Monit ; 27: e931914, 2021 Oct 23.
Article in English | MEDLINE | ID: mdl-34686649

ABSTRACT

BACKGROUND This single-center study aimed to investigate the effects of repetitive transcranial magnetic stimulation (rTMS) on modulation of thyroid hormone levels and cognition in the recovery stage of patients with cognitive dysfunction following stroke. MATERIAL AND METHODS Seventy post-stroke patients who had cognitive impairment were randomly assigned to either the rTMS group or the control (sham) group. Both groups were administered basic treatment, with the rTMS group receiving rTMS (1 Hz, 90% MT, 1000 pulse/20 min, once a day for 5 days, for a total of 20 times), the stimulation site was the contralateral dorsolateral prefrontal cortex (DLPFC), and the sham group receiving sham stimulation which had the same stimulation parameters and site, except that the coil plane was placed perpendicular to the surface of the scalp. Cognitive function assessment and thyroid function tests were performed before and after 4 weeks of treatment. RESULTS Serum levels of triiodothyronine (T3), free triiodothyronine (FT3), and thyroid stimulating hormone (TSH) showed a positive correlation with Montreal Cognitive Assessment (MoCA) scale score of stroke patients in the recovery phase. The post-treatment change in the scores of MoCA and Modified Barthel Index (MBI) and scores of 3 cognitive domains (visuospatial function, memory, and attention), as well as serum T3, FT3, and TSH levels, were improved more significantly in the rTMS group, and T3 and FT3 levels significantly affected the MoCA scores within the reference range. CONCLUSIONS Serum T3, FT3, and TSH levels of stroke patients in the recovery phase were positively correlated with MoCA score. rTMS increased T3, FT3, and TSH levels and also improved MoCA and MBI of patients in the recovery phase of stroke.


Subject(s)
Cognitive Dysfunction , Stroke Rehabilitation/methods , Stroke , Thyroid Hormones/metabolism , Transcranial Magnetic Stimulation/methods , Aged , Cognitive Dysfunction/etiology , Cognitive Dysfunction/therapy , Female , Humans , Male , Middle Aged , Prospective Studies , Stroke/complications , Stroke/therapy
20.
Neoplasma ; 68(1): 62-70, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33118832

ABSTRACT

Aberrant methylation of some genes can serve as promising biomarkers in hepatocellular carcinoma (HCC). This study aimed to investigate the diagnostic and prognostic value of plasma SGIP1 methylation in HCC. The study included a total of 269 subjects, of which 129 were with HCC, 45 with liver cirrhosis (LC), 45 with chronic hepatitis B (CHB), and 50 were healthy controls (HCs). The aberrant methylation was detected by quantitative methylation-specific polymerase chain reaction (qMSP). The area under the curve (AUC) was 0.872 in distinguishing HCC from HCs, with a sensitivity of 85.3% and a specificity of 88%. The AUC was 0.728, when it distinguished HCC from CHB, with a sensitivity of 43.4% and a specificity of 97.8%. The AUC was 0.728 in distinguishing HCC from LC, with a sensitivity of 43.4% and a specificity of 97.8%. Elevated levels of SGIP1 methylation in HCC patients showed poorer overall survival (OS), progression-free survival (PFS), and metastasis-free survival (MFS) than those with low levels (Kaplan-Meier method and the log-rank test, p<0.05). SGIP1 methylation in different study groups demonstrated different sensitivities. SGIP1 methylation detection in the plasma may serve as a non-invasive diagnostic and prognostic biomarker for HCC.


Subject(s)
Adaptor Proteins, Signal Transducing , Carcinoma, Hepatocellular , Liver Neoplasms , Adaptor Proteins, Signal Transducing/blood , Adaptor Proteins, Signal Transducing/genetics , Biomarkers, Tumor/genetics , Carcinoma, Hepatocellular/blood , Carcinoma, Hepatocellular/diagnosis , Carcinoma, Hepatocellular/genetics , DNA Methylation , Humans , Liver Neoplasms/blood , Liver Neoplasms/diagnosis , Liver Neoplasms/genetics , Prognosis , Promoter Regions, Genetic , alpha-Fetoproteins/metabolism
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