1.The dopamine dilemma: Exogenous L-DOPA or rare dopaminoma?
Amal Hanani Abdul Halim ; Farhi Ain Jamaluddin
Journal of the ASEAN Federation of Endocrine Societies 2026;41(S1):22-23
Introduction:
Dopaminomas or dopamine-secreting pheochromocytomas
are rare neuroendocrine tumors that frequently lack the
classic paroxysmal symptoms of catecholamine excess
(headache, sweating, palpitation). Diagnosing these tumors
is exceptionally challenging when biochemical markers—
specifically markedly elevated urinary dopamine—are
interpreted in patients receiving exogenous Levodopa
(L-DOPA) therapy, as the intake obscures clinical
significance.
Case:
A 76-year-old male with ischemic heart disease, stage 4
chronic kidney disease, and new-onset hypertension was
admitted for acute cholecystitis. Imaging studies incidentally revealed bilateral adrenal masses and demonstrated
lipid-rich characteristics upon further evaluation with
computed tomography (CT) adrenal washout. Biochemical
evaluation revealed extreme elevations in 24-hour urinary
dopamine (47,534 nmol/24 hours; normal <3,237) and
3-methoxytyramine (18.93 µmol/24 hours; normal <2.60),
whereas downstream urinary noradrenaline (5.0 nmol/24
hours; normal 71.5–505.3), adrenaline (4.0 nmol/24 hours;
normal 9.2–122.3), normetanephrine (0.22 µmol/24 hours;
normal 0.88–2.88), and metanephrine (0.25 µmol/24 hours;
normal 0.33–1.53) levels were all significantly below their
respective reference ranges. The diagnosis was complicated
by the patient’s concurrent use of L-DOPA/Benserazide
for flupentixol-induced parkinsonism. L-DOPA is a direct
precursor to dopamine; its administration can cause
massive, false-positive elevations in urinary dopamine,
mimicking a dopaminoma’s biochemical signature.
However, the unique combination of profoundly high
dopamine alongside suppressed downstream catecholamines and metanephrines suggested a true dopaminesecreting tumor—potentially secondary to dopamine
beta-hydroxylase (DBH) deficiency—rather than drug
interference.
Conclusion
This case illustrates the profound difficulty in diagnosing
dopaminoma when exogenous L-DOPA therapy creates a
near-identical biochemical profile. The diagnostic dilemma
is further amplified by vague symptomatology, multiple
comorbidities, and non-suggestive imaging. However,
the finding of isolated dopamine hypersecretion with
suppressed metanephrines serves as a critical clinical clue.
This pattern points toward an intratumoral biosynthetic
defect rather than drug interference. Clinicians must
maintain a high index of suspicion and perform meticulous
biochemical fractionation to identify these rare, dopamineisolated secreting tumors.
Dopamine
;
Levodopa
2.Acinetobacter sp. ME1: a multifunctional bacterium for phytoremediation utilizing melanin production, heavy metal tolerance, and plant growth promotion.
Journal of Zhejiang University. Science. B 2025;26(11):1103-1120
Microorganisms inhabiting soils contaminated with heavy metals produce melanin, a dark brown pigment, as a survival strategy. In this study, a melanin-producing bacterium, Acinetobacter sp. ME1, with heavy metal tolerance and plant growth-promoting traits, was isolated from abandoned mine soil. Strain ME1 exhibited growth at concentrations of Zn up to 250 mg/L, Cd and Pb up to 100 mg/L, and Cr up to 50 mg/L. It had the ability to produce the plant hormone indole-3-acetic acid and siderophores along with 1-aminocyclopropane-1-carboxylic acid deaminase and protease activities. Additionally, it showed antioxidant activity, including catalase and 2,2-diphenyl-1-picryhydrazyl (DPPH) scavenging activities. The optimal conditions for melanin production by ME1 were a pH of 7 and a temperature of 35 ℃. At 1000 mg/L, ME1-extracted melanin exhibited DPPH radical scavenging activity of (25.040±0.007)%, a sun protection factor of 15.200±0.260, and 19.6% antibacterial activity against the plant pathogen Xanthomonas campestris. Furthermore, its adsorption capacity was (0.235±0.073) mg/g melanin for Zn and (0.277±0.008) mg/g melanin for Ni. In plants of Brassica chinensis grown under conditions of hydroponic cultivation with single heavy metal contamination of Cd, Zn, Pb, or Cr, the removal efficiency of each heavy metal was improved by 0.1‒1.8 times after 3 d following inoculation with the strain ME1 compared to the plants grown under the same conditions without inoculation. In addition, ME1 inoculation improved the removal efficiency of each heavy metal by 0.1‒1.0 times under multiple heavy metal contamination conditions. These findings suggest that Acinetobacter sp. ME1 could be used to enhance phytoremediation efficiency in heavy metal-contaminated soils. Moreover, the melanin it produces also holds promise in cosmetics, household products, and medical applications due to its photoprotective, antioxidant, and antimicrobial properties.
Acinetobacter/metabolism*
;
Biodegradation, Environmental
;
Metals, Heavy/metabolism*
;
Melanins/metabolism*
;
Soil Microbiology
;
Antioxidants/metabolism*
;
Plant Development
;
Soil Pollutants/metabolism*
;
Indoleacetic Acids/metabolism*
3.Early life Bifidobacterium bifidum BD-1 intervention alleviates hyperactivity of juvenile female rats with attention deficit hyperactivity disorder.
Yang YANG ; Kai WANG ; Jianxiu LIU ; Zhimo ZHOU ; Wen JIA ; Simou WU ; Jinxing LI ; Fang HE ; Ruyue CHENG
Journal of Southern Medical University 2025;45(4):702-710
OBJECTIVES:
To investigate the effects of early life intervention with Bifidobacterium bifidum BD-1 (B. bifidum BD-1) on hyperactivity in a female mouse model of attention deficit hyperactivity disorder (ADHD) and explore the underlying mechanisms.
METHODS:
Eight newborn female Wistar-Kyoto (WKY) rats and 6 spontaneous hypertensive rats (SHRs) were gavaged with saline and another 6 SHRs were gavaged with B. bifidum BD-1 (109 CFU) daily for 3 weeks. Open field test of the rats was conducted at 7 weeks, and fecal samples were collected at weaning (3 weeks) and at 7 weeks for 16S rRNA sequencing. Immunofluorescent staining was used to detect dopamine transporter (DAT) and tyrosine hydroxylase (Th) levels in the striatum and activated microglia in the prefrontal cortex. Treg cells in the mesenteric lymph nodes, spleen and blood were analyzed using flow cytometry.
RESULTS:
The SHRs traveled a significantly greater distance in open fields test than WKY rats, and this behavior was significantly attenuated by B. bifidum BD-1 intervention. The expression of DAT and Th in the striatum was significantly lower in the SHRs than in WKY rats, while B. bifidum BD-1 treatment obviously increased Th levels in the SHRs. B. bifidum BD-1 intervention significantly deceased the number of activated microglia and increased Treg cell counts in the spleen of SHRs. The treatment also enhanced α diversity in gut microbiota of the SHRs and resulted in a decreased Firmicutes/Bacteroidota ratio, more active Muribaculaceae growth, and suppression of Clostridia_UCG-014 proliferation.
CONCLUSIONS
Early life intervention with B. bifidum BD-1 alleviates hyperactivity in female SHRs by modulating the gut microbiota and peripheral immune response, suppressing neuroinflammation and improving dopaminergic system function. These findings provide evidence for early prevention strategies and support the development and application of psychobiotics for ADHD.
Animals
;
Female
;
Rats
;
Rats, Inbred WKY
;
Rats, Inbred SHR
;
Attention Deficit Disorder with Hyperactivity/therapy*
;
Bifidobacterium bifidum
;
Probiotics/therapeutic use*
;
Dopamine Plasma Membrane Transport Proteins/metabolism*
;
Tyrosine 3-Monooxygenase/metabolism*
;
Gastrointestinal Microbiome
;
Disease Models, Animal
4.Local abaloparatide administration promotes in situ alveolar bone augmentation via FAK-mediated periosteal osteogenesis.
Ruyi WANG ; Yuan LI ; Bowen TAN ; Shijia LI ; Yanting WU ; Yao CHEN ; Yuran QIAN ; Haochen WANG ; Bo LI ; Zhihe ZHAO ; Quan YUAN ; Yu LI
International Journal of Oral Science 2025;17(1):63-63
Insufficient alveolar bone thickness increases the risk of periodontal dehiscence and fenestration, especially in orthodontic tooth movement. Abaloparatide (ABL), a synthetic analog of human PTHrP (1-34) and a clinical medication for treating osteoporosis, has recently demonstrated its potential in enhancing craniofacial bone formation. Herein, we show that intraoral submucosal injection of ABL, when combined with mechanical force, promotes in situ alveolar bone thickening. The newly formed bone is primarily located outside the original compact bone, implying its origin from the periosteum. RNA sequencing of the alveolar bone tissue revealed that the focal adhesion (FA) pathway potentially mediates this bioprocess. Local injection of ABL alone enhances cell proliferation, collagen synthesis, and phosphorylation of focal adhesion kinase (FAK) in the alveolar periosteum; when ABL is combined with mechanical force, the FAK expression is upregulated, in line with the accomplishment of the ossification. In vitro, ABL enhances proliferation, migration, and FAK phosphorylation in periosteal stem cells. Furthermore, the pro-osteogenic effects of ABL on alveolar bone are entirely blocked when FAK activity is inhibited by a specific inhibitor. In summary, abaloparatide combined with mechanical force promotes alveolar bone formation via FAK-mediated periosteal osteogenesis. Thus, we have introduced a promising therapeutic approach for drug-induced in situ alveolar bone augmentation, which may prevent or repair the detrimental periodontal dehiscence, holding significant potential in dentistry.
Osteogenesis/drug effects*
;
Periosteum/cytology*
;
Parathyroid Hormone-Related Protein/administration & dosage*
;
Animals
;
Focal Adhesion Protein-Tyrosine Kinases/metabolism*
;
Alveolar Process/drug effects*
;
Cell Proliferation/drug effects*
;
Phosphorylation
;
Rats
;
Male
;
Humans
;
Focal Adhesion Kinase 1/metabolism*
;
Cell Movement/drug effects*
5.Allogeneic hematopoietic stem cell transplantation could overcome the poor prognosis of DNMT3AmutNPM1mutFLT3-ITDmut in acute myeloid leukemia: real-world multicenter analysis in China.
Wenxuan HUO ; Yifan SHEN ; Jiayu HUANG ; Yang YANG ; Shuang FAN ; Xiaosu ZHAO ; Qi WEN ; Luxiang WANG ; Chuanhe JIANG ; Yang CAO ; Xiaodong MO ; Yang XU ; Xiaoxia HU
Frontiers of Medicine 2025;19(1):90-100
The cooccurrence of NPM1, FLT3-ITD, and DNMT3A mutations (i.e., triple mutation) is related to dismal prognosis in patients with acute myeloid leukemia (AML) receiving chemotherapy alone. In this multicenter retrospective cohort study, we aimed to identify whether allogeneic hematopoietic stem cell transplantation (allo-HSCT) could overcome the poor prognosis of DNMT3AmutNPM1mutFLT3-ITDmut AML across four transplant centers in China. Fifty-three patients with triple-mutated AML receiving allo-HSCT in complete remission were enrolled. The 1.5-year probabilities of relapse, leukemia-free survival, and overall survival after allo-HSCT were 11.9%, 80.3%, and 81.8%, respectively. Multivariate analysis revealed that more than one course of induction chemotherapy and allo-HSCT beyond CR1 were associated with poor survival. To our knowledge, this work is the largest study to explore the up-to-date undefined role of allo-HSCT in patients with triple-mutated AML. Our real-world data suggest that allo-HSCT could overcome the poor prognosis of DNMT3AmutNPM1mutFLT3-ITDmut in AML.
Humans
;
Nucleophosmin
;
Leukemia, Myeloid, Acute/mortality*
;
Hematopoietic Stem Cell Transplantation/methods*
;
Male
;
Female
;
DNA Methyltransferase 3A
;
Adult
;
China
;
Retrospective Studies
;
DNA (Cytosine-5-)-Methyltransferases/genetics*
;
Middle Aged
;
Prognosis
;
fms-Like Tyrosine Kinase 3/genetics*
;
Mutation
;
Young Adult
;
Transplantation, Homologous
;
Nuclear Proteins/genetics*
;
Adolescent
;
Aged
6.Nigella sativa L. seed extract alleviates oxidative stress-induced cellular senescence and dysfunction in melanocytes.
Ben NIU ; Xiaohong AN ; Yongmei CHEN ; Ting HE ; Xiao ZHAN ; Xiuqi ZHU ; Fengfeng PING ; Wei ZHANG ; Jia ZHOU
Chinese Journal of Natural Medicines (English Ed.) 2025;23(2):203-213
Nigella sativa L. seeds have been traditionally utilized in Chinese folk medicine for centuries to treat vitiligo. This study revealed that the ethanolic extract of Nigella sativa L. (HZC) enhances melanogenesis and mitigates oxidative stress-induced cellular senescence and dysfunction in melanocytes. In accordance with established protocols, the ethanol fraction from Nigella sativa L. seeds was extracted, concentrated, and lyophilized to evaluate its herbal effects via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, tyrosinase activity evaluation, measurement of cellular melanin contents, scratch assays, senescence-associated β-galactosidase (SA-β-gal) staining, enzyme-linked immunosorbent assay (ELISA), and Western blot analysis for expression profiling of experimentally relevant proteins. The results indicated that HZC significantly enhanced tyrosinase activity and melanin content while notably increasing the protein expression levels of Tyr, Mitf, and gp100 in B16F10 cells. Furthermore, HZC effectively mitigated oxidative stress-induced cellular senescence, improved melanocyte condition, and rectified various functional impairments associated with melanocyte dysfunction. These findings suggest that HZC increases melanin synthesis in melanocytes through the activation of the MAPK, PKA, and Wnt signaling pathways. In addition, HZC attenuates oxidative damage induced by H2O2 therapy by activating the nuclear factor E2-related factor 2-antioxidant response element (Nrf2-ARE) pathway and enhancing the activity of downstream antioxidant enzymes, thus preventing premature senescence and dysfunction in melanocytes.
Oxidative Stress/drug effects*
;
Melanocytes/cytology*
;
Cellular Senescence/drug effects*
;
Nigella sativa/chemistry*
;
Plant Extracts/pharmacology*
;
Seeds/chemistry*
;
Mice
;
Animals
;
Melanins/metabolism*
;
Monophenol Monooxygenase/metabolism*
;
Humans
7.Neuroprotective and antidiabetic lanostane-type triterpenoids from the fruiting bodies of Ganoderma theaecolum.
Jiaocen GUO ; Li YANG ; Luting DAI ; Qingyun MA ; Jiaoyang YAN ; Qingyi XIE ; Yougen WU ; Haofu DAI ; Youxing ZHAO
Chinese Journal of Natural Medicines (English Ed.) 2025;23(2):245-256
Eight previously undescribed lanostane triterpenoids, including five nortriterpenoids with 26 carbons, ganothenoids A-E (1-5), and three lanostanoids, ganothenoids F-H (6-8), along with 24 known ones (9-32), were isolated from the fruiting bodies of Ganodrma theaecolum. The structures of the novel compounds were elucidated using comprehensive spectroscopic methods, including electronic circular dichroism (ECD) and nuclear magnetic resonance (NMR) calculations. Compounds 1-32 were assessed for their neuroprotective effects against H2O2-induced damage in human neuroblastoma SH-SY5Y cells, as well as their inhibitory activities against protein tyrosine phosphatase 1B (PTP1B) and α-glucosidase. Compound 4 demonstrated the most potent neuroprotective activity against H2O2-induced oxidative stress by suppressing G0/G1 phase cell cycle arrest, reducing reactive oxygen species (ROS) levels, and inhibiting cell apoptosis through modulation of B-cell lymphoma 2 protein (Bcl-2) and Bcl-2 associated X-protein (Bax) protein expression. Compounds 26, 12, and 28 exhibited PTP1B inhibitory activities with IC50 values ranging from 13.92 to 56.94 μmol·L-1, while compound 12 alone displayed significant inhibitory effects on α-glucosidase with an IC50 value of 43.56 μmol·L-1. Additionally, enzyme kinetic analyses and molecular docking simulations were conducted for compounds 26 and 12 with PTP1B and α-glucosidase, respectively.
Humans
;
Fruiting Bodies, Fungal/chemistry*
;
Triterpenes/isolation & purification*
;
Neuroprotective Agents/isolation & purification*
;
Protein Tyrosine Phosphatase, Non-Receptor Type 1/metabolism*
;
Ganoderma/chemistry*
;
Apoptosis/drug effects*
;
Hypoglycemic Agents/isolation & purification*
;
Molecular Structure
;
alpha-Glucosidases/metabolism*
;
Cell Line, Tumor
;
Reactive Oxygen Species/metabolism*
;
Oxidative Stress/drug effects*
;
Hydrogen Peroxide/toxicity*
;
Molecular Docking Simulation
8.Whole-cell transformation for the synthesis of tyrosine by a multi-enzyme cascade.
Fei YANG ; Yue WANG ; Xuanping SHI ; Jiajia YOU ; Minglong SHAO ; Meijuan XU ; Zhiming RAO
Chinese Journal of Biotechnology 2025;41(9):3537-3552
L-tyrosine is one of the 20 amino acids that make up proteins and is an essential amino acid for mammals, often used as a nutritional supplement. The conventional methods for synthesizing L-tyrosine have some problems such as the production of many by-products, high requirements for production conditions, and environmental pollution. In this study, we designed and constructed a multi-enzyme cascade for the synthesis of L-tyrosine with alanine, glutamate, ammonium chloride, and phenol as substrates. Initially, the sources of glutamate oxidase, alanine aminotransferase, and tyrosine phenol lyase were screened and analyzed, which was followed by the identification of the rate-limiting enzyme in the reaction process. A colorimetric screening method was established, and the rate-limiting enzyme DbAlaA was engineered to enhance its activity by 40.0%. Subsequently, the reaction conditions, including temperature, pH, cell concentration, and surfactant and coenzyme dosages, were optimized. After optimization, the yield of L-tyrosine reached 9.93 g/L, with a alanine conversion rate of 54.90%. Finally, a feed-batch fermentation strategy was adopted, and the yield of L-tyrosine reached 56.07 g/L after 24 h, with a alanine conversion rate of 65.22%. This study provides a reference for the whole-cell catalytic synthesis of L-tyrosine and its industrialization.
Tyrosine/biosynthesis*
;
Escherichia coli/metabolism*
;
Tyrosine Phenol-Lyase/genetics*
;
Multienzyme Complexes/metabolism*
;
Fermentation
9.Signature motif identification and enzymatic characterization of a protein tyrosine phosphatase in Metarhizium anisopliae.
Ze TAN ; Pei ZHU ; Zhenlun LI ; Shuiying YANG
Chinese Journal of Biotechnology 2025;41(9):3579-3588
Protein tyrosine phosphatases (PTPs, EC 3.1.3.48) are key regulators of cellular processes, with the catalytic activity attributed to the conserved motif (H/V)CX5R(S/T), where cysteine and arginine residues are critical. Previous studies revealed that alternative splicing of extracellular phosphatase mRNA precursors in Metarhizium anisopliae generated two distinct transcripts, with the longer sequence containing a novel HCPTPMLS motif resembling PTP signatures but lacking the arginine residue. To identify the novel signature motif and characterize its enzymatic properties, we heterologously expressed and purified both proteins in Pichia pastoris and comprehensively characterized their enzymatic properties. The protein containing the HCPTPMLS motif (designated as L-protein) exhibited the highest activity at pH 5.5 and a strong preference for pTyr substrates. Its phosphatase activity was inhibited by Ag+, Zn2+, Cu2+, molybdate, and tungstate, but enhanced by Ca2+ and EDTA. AcP101 (lacking HCPTPMLS) showed the maximal activity at pH 6.5 and a strong preference toward pNPP (P < 0.05), with the activity inhibited by NaF and tartrate, but enhanced by Mg2+ and Mn2+. Functional analysis confirmed that the L-protein retained the PTP activity despite the absence of arginine in its signature motif, while AcP101 functioned as an acid phosphatase. This study provides the first functional validation of an arginine-deficient PTP motif, expanding the definition of PTP signature motifs and offering new insights for phosphatase classification.
Metarhizium/genetics*
;
Protein Tyrosine Phosphatases/chemistry*
;
Amino Acid Motifs
;
Recombinant Proteins/biosynthesis*
;
Amino Acid Sequence
;
Pichia/metabolism*
;
Fungal Proteins/chemistry*
;
Substrate Specificity
;
Saccharomycetales
10.Clinical features of dyskinesis and related risk factors in female patients with Parkinson disease
Journal of Apoplexy and Nervous Diseases 2025;42(2):109-114
Objective To investigate the clinical features of dyskinesia and related risk factors in female patients with Parkinson disease (PD). Methods A cross-sectional study was conducted among the female patients who met the diagnostic criteria for PD at the outpatient service of PD in Aerospace Center Hospital, and demographic data and clinical data were collected and compared between groups, including levodopa equivalent daily dose (LEDD), Unified Parkinson’s Disease Rating Scale-Ⅲ(UPDRS-Ⅲ), UPDRS-Ⅳ, scores of non-motor symptoms (cognition and depression), presence or absence of dyskinesia, and single levodopa dose (LD) during the onset of dyskinesia. A binary logistic regression analysis was used to investigate the influencing factors for dyskinesia in female patients with PD. Results A total of 146 female PD patients were enrolled, among whom 30 patients had dyskinesia, with an incidence rate of 20.5%. Compared with the non-dyskinesia group in terms of clinical features, the dyskinesia group had a significantly younger age of onset [(54.3±12.5) years vs (62.7±10.0) years, P<0.001], a significantly longer disease duration [(9.9±3.7) years vs (4.5±3.7) years, P<0.001], a significantly higher severity of disease [H-Y stage: (2.65±0.58) vs (2.35±0.83), P=0.03], a significantly longer duration of LD administration [(7.5±3.2) years vs (3.2±2.6) years, P<0.001], a significantly higher LEDD [(703.2±203.9) mg vs (442.1±226.3) mg, P<0.001], and significantly lower body weight [(54.1±8.2) kg vs (60.0±8.7) kg, P=0.001] and BMI [(20.9±3.1) kg/m2 vs (23.4±3.1) kg/m2, P<0.001]. The multivariate logistic regression analysis showed that high BMI (OR=0.770, P=0.005) was a protective factor against dyskinesia in female PD patients, while long disease duration (OR=1.304, P=0.001) and high LEDD (OR=1.003, P=0.012) were risk factors for dyskinesia. Conclusion There is a relatively high incidence rate of dyskinesia in female PD patients, which should be taken seriously in clinical practice, and high BMI is a protective factor, while long disease duration and high LEDD are risk factors for dyskinesia in female PD patients.
Parkinson Disease
;
Dyskinesias
;
Levodopa


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