1.Mitochondria: The Target of Ionizing Radiation Damage
Lian-Chen TIAN ; Ya-Yi YUAN ; Xu-Hong DANG
Progress in Biochemistry and Biophysics 2025;52(4):836-844
In recent years, due to the development of radiotherapy technology and nuclear energy, people have paid more and more attention to the various effects of ionizing radiation on organisms. Ionizing radiation can induce protein, DNA and other biological macromolecules to damage, resulting in apoptosis, senescence, cancer and a series of changes. For a long time, it has been believed that the main target of ionizing radiation damage is DNA in the nucleus. However, it has been reported in recent years that ionizing radiation has both direct and indirect effects, and the theory of ROS damage in the indirect effects believes that ionizing radiation has target uncertainty, so it is not comprehensive enough to evaluate only the DNA damage in the nucleus. It has been reported that ionizing radiation can cause damage to organelles as well as damage to cells. Mitochondria are important damaged organelles because mitochondria occupy as much as 30% of the entire cell volume in the cytoplasm, which contains DNA and related enzymes that are closely related to cellular ATP synthesis, aerobic respiration and other life activities. What is more noteworthy is that mitochondria are the only organelles in which DNA exists in the human body, which makes researchers pay attention to various damage to mitochondrial DNA caused by ionizing radiation (such as double-strand breaks, base mismatching, and fragment loss). Although these damages also occur in the nucleus, mitochondrial DNA is more severely damaged than nuclear DNA due to its lack of histone protection, so mitochondria are important targets of ionizing radiation damage in addition to the nucleus. Mitochondrial DNA is not protected by histones and has little repair ability. When exposed to ionizing radiation, common deletions occur at an increased frequency and are passed on to offspring. For large-scale mitochondrial DNA damage, mitochondria indirectly compensate for the amount of damaged DNA by increasing the number of DNA copies and maintaining the normal function of mitochondrial DNA. Mitochondria are in a state of oxidative stress after exposure to ionizing radiation, and this oxidative stress will promote the change in mitochondrial function. When mitochondria are damaged, the activity of proteins related to aerobic respiration decreases, and oxidative respiration is inhibited to a certain extent. At the same time, a large amount of active superoxide anions are continuously produced to stimulate mitochondrial oxidative stress, and the signal of such damage is transmitted to the surrounding mitochondria, resulting in a cascade of damage reaction, which further activates the signalling pathway between mitochondria and nucleus. The cell nucleus is also in a state of oxidative stress, and finally, the level of free radicals is high, causing secondary damage to the genetic material DNA of mitochondria and nucleus. In this paper, the damage effects of ionizing radiation on mitochondria are reviewed, to provide a new idea for radiation protection.
2.Role and mechanism of platelet-derived growth factor BB in repair of growth plate injury
Hongcheng PENG ; Guoxuan PENG ; Anyi LEI ; Yuan LIN ; Hong SUN ; Xu NING ; Xianwen SHANG ; Jin DENG ; Mingzhi HUANG
Chinese Journal of Tissue Engineering Research 2025;29(7):1497-1503
BACKGROUND:In the initial stage of growth plate injury inflammation,platelet-derived growth factor BB promotes the repair of growth plate injury by promoting mesenchymal progenitor cell infiltration,chondrogenesis,osteogenic response,and regulating bone remodeling. OBJECTIVE:To elucidate the action mechanism of platelet-derived growth factor BB after growth plate injury. METHODS:PubMed,VIP,WanFang,and CNKI databases were used as the literature sources.The search terms were"growth plate injury,bone bridge,platelet-derived growth factor BB,repair"in English and Chinese.Finally,66 articles were screened for this review. RESULTS AND CONCLUSION:Growth plate injury experienced early inflammation,vascular reconstruction,fibroossification,structural remodeling and other pathological processes,accompanied by the crosstalk of chondrocytes,vascular endothelial cells,stem cells,osteoblasts,osteoclasts and other cells.Platelet-derived growth factor BB,as an important factor in the early inflammatory response of injury,regulates the injury repair process by mediating a variety of cellular inflammatory responses.Targeting the inflammatory stimulation mediated by platelet-derived growth factor BB may delay the bone bridge formation process by improving the functional activities of osteoclasts,osteoblasts,and chondrocytes,so as to achieve the injury repair of growth plate.Platelet-derived growth factor BB plays an important role in angiogenesis and bone repair tissue formation at the injured site of growth plate and intrachondral bone lengthening function of uninjured growth plate.Inhibition of the coupling effect between angiogenesis initiated by platelet-derived growth factor BB and intrachondral bone formation may achieve the repair of growth plate injury.
3.Preliminary study on the biological characteristics of heat shock cognate protein 20 of Schistosoma japonicum
Xingang YU ; Kaijian YUAN ; Yilong LI ; Xuanru MU ; Hui XU ; Qiaoyu LI ; Wenjing ZENG ; Zhiqiang FU ; Yang HONG
Chinese Journal of Schistosomiasis Control 2025;37(3):294-303
Objective To clone and express the heat shock cognate protein 20 (SjHsc20) of Schistosoma japonicum, and to preliminarily investigate its biological characteristics. Methods The target fragment of the SjHsc20 gene was amplified using PCR assay and cloned into the pET-28a(+) expression plasmid to generate the recombinant expression vector pET-28a(+)-SjH-sc20, which was then transformed into Escherichia coli BL21 (DE3) competent cells. The recombinant SjHsc20 (rSjHsc20) protein was induced with isopropyl β-D-thiogalactopyranoside (IPTG) and purified, and the expression of the rSjHsc20 protein was checked with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The immunogenicity of the rSjHsc20 protein was detected using Western blotting, and the transcriptional levels of SjHsc20 were quantified in S. japonicum worms at different developmental stages and in male and female adult worms using real-time quantitative PCR (RT-qPCR) assay. Thirty female BALB/c mice at ages 6 to 8 weeks were divided into three groups, including the rSjHsc20 immunization group, the PBS control group, and the ISA 206 adjuvant group, of 10 mice in each group. Mice in the rSjHsc20 immunization group were subcutaneously immunized with 20 μg rSjHsc20 on days 1, 15 and 31, and animals in the PBS control group were subcutaneously injected with the same volume of PBS on days 1, 15 and 31, while mice in the ISA 206 adjuvant group were subcutaneously immunized with the same volume of ISA 206 adjuvant on days 1, 15 and 31, respectively. All mice in each group were infected with (40 ± 2) S. japonicum cercariae via the abdomen 14 day following the last immunization. Levels of serum specific IgG and its subtypes IgG1 and IgG2 antibodies against rSjHsc20, and the serum titers of anti-rSjHsc20 antibody were detected in mice using indirect enzyme-linked immunosorbent assay (ELISA). All mice were sacrifice 42 days post-infection, and S. japonicum worms were collected from the hepatic portal vein and counted. The eggs per gram (EPG), worm burden reductions and egg burden reductions were estimated to evaluate the protective efficacy of the rSjHsc20 protein. Results The SjHsc20 gene had an open reading frame (ORF) with 756 bp in length and encoded 252 amino acids, and the rSjHsc20 protein had a relative molecular mass of approximately 29 kDa. The rSjHsc20 protein was recognized by the serum of mice infected with S. japonicum and the serum of mice immunized with the rSjHsc20 protein, indicating that rSjHsc20 had a good immunogenicity. There was a significant difference in the transcriptional levels of the SjHsc20 gene among the 7-day (1.001 4 ± 0.065 7), 12-day (2.268 3 ± 0.129 2), 21-day (1.378 5 ± 0.160 4), 28-day (1.196 4 ± 0.244 0), 35-day (1.646 3 ± 0.226 1), 42-day worms of S. japonicum (1.758 0 ± 0.611 1) (F = 38.45, P < 0.000 1), and the transcriptional level of the SjHsc20 gene was higher in the 12-day worms than in worms at other developmental stages (all P values < 0.000 1). The serum levels of anti-rSjHsc20 IgG antibody were 0.106 6 ± 0.010 7, 0.108 3 ± 0.010 4, and 0.553 2 ± 0.069 1 in the PBS control group, ISA 206 adjuvant group, and rSjHsc20 immunization group following the last immunization, respectively, and the serum levels of IgG1 antibody were 0.137 3 ± 0.054 0, 0.181 1 ± 0.096 8, and 1.765 8 ± 0.221 1, while the levels of IgG2a antibody were 0.280 3 ± 0.197 6, 0.274 0 ± 0.146 3, and 1.560 4 ± 0.106 0, respectively. There were significant differences in the serum levels of anti-rSjHsc20 IgG (F = 397.70, P < 0.000 1), IgG1 (F = 401.00, P < 0.000 1) and IgG2a antibodies (F = 229.70, P < 0.000 1) among the three groups, and the serum levels of anti-rSjHsc20 IgG, IgG1 and IgG2a antibodies were higher in the rSjHsc20 immunization group than in the PBS control group and the ISA 206 adjuvant group (all P values < 0.000 1). There was a significant difference in the IgG1/IgG2a ratio among the rSjHsc20 immunization group (1.177 2 ± 0.143 6), the PBS control group (0.428 4 ± 0.199 8) and the ISA 206 adjuvant group (0.559 9 ± 0.181 1) (F = 43.97, P < 0.000 1), and the IgG1/IgG2a ratio was > 1 in the rSjHsc20 immunization group, which was higher than in the PBS control group and the ISA 206 adjuvant group (both P values < 0.000 1). The titers of serum anti-rSjHsc20 antibody were all above 1∶16 384 in the rSjHsc20 immunization group following immunizations on days 1, 15 and 31, indicating that the rSjHsc20 protein had a strong immunogenicity. The mean worm burdens were (16.60±5.75), (15.80±5.58) worms per mouse and (14.40±5.75) worms per mouse in the PBS control group, the ISA 206 adjuvant group and the rSjHsc20 immunization group 42 days post-infection with S. japonicum cercariae (F = 0.50, P > 0.05), and the EPG were 68 370 ± 22 690, 67 972 ± 19 502, and 41 075 ± 13 251 in the PBS control group, the ISA 206 adjuvant group and the rSjHsc20 immunization group (F = 4.55, P < 0.05), with lower EPG in the PBS control group and the ISA 206 adjuvant group than in the rSjHsc20 immunization group (both P values < 0.05). Immunization with the rSjHsc20 protein resulted in a worm burden reduction of 13.25% and an egg burden reduction of 39.92% relative to the PBS control group. Conclusions SjHsc20 is successfully cloned and expressed, and the rSjHsc20 protein induces partial immunoprotective effects in mice, which provides a basis for deciphering the biological functions of SjHsc20 and assessing the potential of SjH-sc20 as a vaccine candidate.
4.Clinical characteristics analysis on clinical high-risk patients with bipolar disorder
Shengmin ZHANG ; Xinyu MENG ; Yingzhen XU ; Jingwen SUN ; Zhikang MAO ; Shuzhe ZHOU ; Tianhang ZHOU ; Yilin YUAN ; Chenmei XIE ; Xinrui ZHAO ; Yantao MA ; Hong MA ; Xin YU ; Lili GUAN
Journal of Jilin University(Medicine Edition) 2025;51(4):1061-1071
Objective:To compare the differences in clinical characteristics among the patients at clinical high risk for bipolar disorder(CHR-BD),the patients with bipolar disorder(BD),and the healthy controls(HC)at low risk,and to provide the basis for the diognasis and treatment of CHR-BD.Methods:For the first time,the BD risk criteria and prospective structured assessment tools were jointly used in outpatients aged 16-30 years,and 43 CHR-BD patients were included to ensure the accuracy of the assessment.Meanwhile,33 BD patients and 32 HC subjects were also enrolled.The clinical symptoms,neurocognitive function,and global functional levels of the subjects in the three groups were evaluated using observer-rated and self-rated tools.The CHR-BD and BD groups were combined,and Logistic regression analysis was used to identify the independent influencing factors related to diagnostic status;Pearson or Spearman correlation analysis was used to analyze the correlations between the global functional levels and the symptoms or neurocognitive characteristics of the patients in CHR-BD and BD groups.Results:There were statistically significant differences in the scores of symptom and global functional level scales among HC,CHR-BD,and BD groups(P<0.05).Compared with HC group,the scores of mood symptoms(anxiety,depression,and mania/hypomania),psychotic symptoms,total affective temperament questionnaire scores,and some dimensions(cyclothymic,depressive,irritable,and anxious temperaments)in CHR-BD and BD groups were significantly increased(P<0.001),while the global functional levels were significantly decreased(P<0.001).Compared with BD group,the lowest global functional level score in the past year in CHR-BD group was significantly increased(P=0.022),while the current global functional level score was significantly decreased(P=0.005).No significant differences were observed in neurocognitive function scores among the three groups(P>0.05).The lowest global functional level score in the past year was an independent influencing factor for BD diagnosis[odds ratio(OR)=0.952,95%confidence interval(CI):0.917-0.988,P=0.010].In both CHR-BD and BD patients,the current global functional levels were negatively correlated with depressive(r=-0.417,P=0.005;r=-0.617,P<0.001)and anxiety symptoms(r=-0.360,P=0.018;r=-0.506,P=0.003).In BD patients,the current global functional level was negatively correlated with lifetime manic/hypomanic symptoms(r=-0.360,P=0.039),psychotic symptoms(r=-0.502,P=0.003),and affective temperament scores(r=-0.479,P=0.005),while the lowest global functional level in the past year was negatively correlated with lifetime manic/hypomanic symptoms(r=-0.391,P=0.024).Conclusion:CHR-BD patients share similar mood symptom characteristics with BD patients,and their global functional levels are negatively correlated with depressive and anxiety symptoms.BD patients exhibit worse lowest global functional levels in the past year,and their global functional levels are negatively correlated with manic/hypomanic symptoms.
5.Investigation of an outbreak of group A human G9P [8] rotavirus infectious diarrhea among adults in Chongqing
Yang WANG ; Yuan KONG ; Ning CHEN ; Lundi YANG ; Jiang LONG ; Qin LI ; Xiaoyang XU ; Wei ZHENG ; Hong WEI ; Jie LU ; Quanjie XIAO ; Yingying BA ; Wenxi WU ; Qian XU ; Ju YAN
Shanghai Journal of Preventive Medicine 2025;37(8):663-668
ObjectiveTo investigate and analyze an outbreak of rotavirus infectious diarrhea in a prison in Chongqing Municipality, to provide a basis for adult rotavirus surveillance and prevention, and to explore the public health problems in special settings. MethodsA retrospective survey was conducted to collect and analyze data on individual cases with diarrheal disease on-site. The clinical characteristics, as well as the temporal, spatial and geographical distribution patterns of the epidemic were described. Multi-pathogen detection tests were conducted both on diarrhea cases and environmental samples, with viral genotyping performed on positive samples. A case-control analysis was performed to identify the causes of the outbreak, and an SEIR model was adopted to predict the outbreak trend and evaluate the effectiveness of interventions. ResultsA total of 65 cases were found among the inmates, with an attack rate of 2.03%. The predominant clinical manifestations included diarrhea (89.23%), watery stool (73.85%), and dehydration (18.46%). The epidemic curve indicated a “human-to-human” transmission pattern, with an average incubation period of 5‒6 days. The attack rates among chefs in the main canteen (80.00%, 8/10) and caterers (28.33%, 17/60) were significantly higher than those of other inmates (P<0.05). Multi-pathogen polymerase chain reaction (PCR) testing detected positive for group A rotavirus, with the viral genotyping identified as G9P [8] strain. Factors such as unprotected "bare-handed" food distribution among cases with diarrhea (OR=9.512, 95%CI: 4.261‒21.234) and close contact with diarrhea cases (OR=3.656, 95%CI: 1.719‒7.778) were the possible cause of the outbreak. The SEIR model (r0=5, α=0.3, β1=0.08, β2=0.04) was constructed using prison inmates as susceptible population, aiming at fitting the initial transmission trend of the outbreak, and the epidemic rate declined rapidly after intervention measures were implemented (rt≈0). ConclusionThis rare rotavirus infection diarrhea outbreak among adults in confined settings suggests that the construction of public health prevention and control systems in prison may be overlooked. Cross infection during meal processing and distribution in the canteens of such settings is likely to be the cause of the outbreak. Given the potential neglect of public heath system construction in special settings, it is imperative to enhance the surveillance and monitoring of rotavirus and other intestinal multi-pathogens among adults, as well as the construction of public health prevention and control systems in these special settings.
6.De novo patients with high-volume metastatic hormone-sensitive prostate cancer can benefit from the addition of docetaxel to triplet therapy: Network-analysis and systematic review.
Hanxu GUO ; Chengqi JIN ; Li DING ; Jun XIE ; Jing XU ; Ruiliang WANG ; Hong WANG ; Changcheng GUO ; Jiansheng ZHANG ; Bo PENG ; Xudong YAO ; Jing YUAN ; Bin YANG
Chinese Medical Journal 2025;138(2):231-233
7.Cold stimulation regulates lipid metabolism and the secretion of exosomes from subcutaneous adipose tissue in mice.
Shuo KE ; Li XU ; Rui-Xue SHI ; Jia-Qi WANG ; Le CUI ; Yuan JI ; Jing LI ; Xiao-Hong JIANG
Acta Physiologica Sinica 2025;77(2):231-240
Cold has been a long-term survival challenge in the evolutionary process of mammals. In response to cold stress, in addition to brown adipose tissue (BAT) dissipating energy as heat through glucose and lipid oxidation to maintain body temperature, cold stimulation can strongly activate thermogenesis and energy expenditure in beige fat cells, which are widely distributed in the subcutaneous layer. However, the effects of cold stimulation on other tissues and systemic lipid metabolism remain unclear. Our previous research indicated that, under cold stress, BAT not only produces heat but also secretes numerous exosomes to mediate BAT-liver crosstalk. Whether subcutaneous fat has a similar mechanism is still unknown. Therefore, this study aimed to investigate the alterations in lipid metabolism across various tissues under cold exposure and to explore whether subcutaneous fat regulates systemic glucose and lipid metabolism via exosomes, thereby elucidating the regulatory mechanisms of lipid metabolism homeostasis under physiological stress. RT-qPCR, Western blot, and H&E staining methods were used to investigate the physiological changes in lipid metabolism in the serum, liver, epididymal white adipose tissue, and subcutaneous fat of mice under cold stimulation. The results revealed that cold exposure significantly enhanced the thermogenic activity of subcutaneous adipose tissue and markedly increased exosome secretion. These exosomes were efficiently taken up by hepatocytes, where they profoundly influenced hepatic lipid metabolism, as evidenced by alterations in the expression levels of key genes involved in lipid synthesis and catabolism pathways. This study has unveiled a novel mechanism by which subcutaneous fat regulates lipid metabolism through exosome secretion under cold stimulation, providing new insights into the systemic regulatory role of beige adipocytes under cold stress and offering a theoretical basis for the development of new therapeutic strategies for obesity and metabolic diseases.
Animals
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Lipid Metabolism/physiology*
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Mice
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Exosomes/metabolism*
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Cold Temperature
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Subcutaneous Fat/physiology*
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Thermogenesis/physiology*
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Adipose Tissue, Brown/metabolism*
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Male
8.Angelicae Dahuricae Radix polysaccharides treat ulcerative colitis in mice by regulating gut microbiota and metabolism.
Feng XU ; Lei ZHU ; Ya-Nan LI ; Cheng CHENG ; Yuan CUI ; Yi-Heng TONG ; Jing-Yi HU ; Hong SHEN
China Journal of Chinese Materia Medica 2025;50(4):896-907
This study employed 16S r RNA gene high-throughput sequencing and metabolomics to explore the mechanism of Angelicae Dahuricae Radix polysaccharides(RP) in the treatment of ulcerative colitis(UC). A mouse model of UC was induced with 2. 5% dextran sulfate sodium. The therapeutic effects of RP on UC in mice were evaluated based on changes in body weight, disease activity index( DAI), and colon length, as well as pathological changes. RT-qPCR was performed to assess the m RNA levels of interleukin(IL)-6, IL-1β, tumor necrosis factor(TNF)-α, myeloperoxidase(MPO), mucin 2(Muc2), Occludin, Claudin2, and ZO-1 in the mouse colon tissue. ELISA was employed to measure the expression of IL-1β and TNF-α in the colon tissue. The intestinal permeability of mice was evaluated by the fluorescent dye permeability assay. Immunohistochemistry was employed to detect the expression of Muc2 and occludin in the colon tissue. Changes in gut microbiota and metabolites were analyzed by 16S r RNA sequencing and ultra-high-performance liquid chromatography coupled with quadrupole-orbitrap mass spectrometry( UPLC-Q-Exactive Plus Orbitrap MS), respectively. The results indicated that low-dose RP alleviated general symptoms, reduced colonic inflammation and intestinal permeability, and promoted Muc2 secretion and tight junction protein expression in UC mice. In addition, low-dose RP increased gut microbiota diversity in UC mice and decreased the relative abundance of harmful bacteria such as Ochrobactrum and Streptococcus. Twenty-seven differential metabolites were identified in feces, and low-dose RP restored the levels of disturbed metabolites. Notably, arginine and proline metabolism were the most significantly altered amino acid metabolic pathways following lowdose RP intervention. In conclusion, RP can ameliorate general symptoms, inhibit colonic inflammation, and maintain intestinal mucosal barrier integrity in UC mice by modulating gut microbiota composition and arginine and proline metabolism.
Animals
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Gastrointestinal Microbiome/drug effects*
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Colitis, Ulcerative/genetics*
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Mice
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Male
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Drugs, Chinese Herbal/administration & dosage*
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Polysaccharides/administration & dosage*
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Angelica/chemistry*
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Humans
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Colon/metabolism*
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Disease Models, Animal
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Mucin-2/metabolism*
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Tumor Necrosis Factor-alpha/metabolism*
9.Effects of understory environmental factors on understory planting of medicinal plants.
Ding-Mei WEN ; Hong-Biao ZHANG ; Feng-Yuan QIN ; Chao-Qun XU ; Dou-Dou LI ; Bao-Lin GUO
China Journal of Chinese Materia Medica 2025;50(5):1164-1171
Understory planting of medicinal plants is a new planting mode that connects Chinese herbal medicine(CHM) with forest resources.The complex and variable understory environmental factors will inevitably affect the yield and quality of understory CHM.This research summarized the research progress on understory planting of medicinal plants based on forest types and environmental factors within the forest from the perspectives of understory light, air temperature and humidity, soil characteristics, and the interaction between crops within the forest.The results showed that the complex and variable light, temperature and humidity, and soil factors(such as fertility, acidity and alkalinity, and microorganisms) under the forest could affect the yield and quality of medicinal plants to varying degrees through physiological activities such as photosynthesis and respiration, resulting in a significant increase or decrease in yield and quality compared to open field cultivation.In addition, the competition or mutual benefit between different crops within the forest could lead to differences in the yield and quality of understory medicinal plants compared to open field cultivation.A reasonable combination of planting could achieve resource sharing and complementary advantages.Therefore, conducting systematic research on the effects of understory environmental factors on the yield and content of medicinal plants with different growth and development characteristics can provide theoretical guidance and technical references for formulating comprehensive strategies for understory planting of medicinal plants, such as selecting suitable medicinal plant varieties, optimizing planting density, and conducting reasonable forest management, thus contributing to the sustainable development and ecological protection of CHM.
Plants, Medicinal/growth & development*
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Forests
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Soil/chemistry*
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Environment
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Ecosystem
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Temperature
10.Synthesis of active substance 3,4-dihydroxyacetophenone from traditional Chinese medicine using Escherichia coli whole-cell bioconversion of 1-(4-hydroxyphenol)-ethanol.
Xi-Wei YUAN ; Yan-Qiu TIAN ; Wen-Yu WANG ; Ya-Lun ZHANG ; De-Hong XU
China Journal of Chinese Materia Medica 2025;50(5):1187-1194
The main active compound, 3,4-dihydroxyacetophenone(3,4-DHAP), in the leaves of Ilex pubescens var. glaber, exhibits various pharmacological activities, including vasodilation and heart protection. Currently, natural extraction and chemical synthesis are the primary methods for obtaining 3,4-DHAP, but both approaches have inherent challenges. To address these problems, this study explored the whole-cell bioconversion of 1-(4-hydroxyphenol)-ethanol to 3,4-DHAP using recombinant Escherichia coli, cultivated in a green, cost-effective medium at room temperature and atmospheric pressure. Firstly, this study successfully constructed recombinant E. coli S1, which contained only the HpaBC gene, and recombinant E. coli S3, which contained both the Hped and HpaBC genes. The ability of S1 and S3 to synthesize 3,4-DHAP from their respective substrates was then evaluated through whole-cell bioconversion. Based on these results, the effects of four factors, i.e., substrate concentration, IPTG concentration, induction temperature, and transformation temperature, on the whole-cell bioconversion yield of S3 were investigated using an orthogonal experiment. The results showed that the factors influenced the yield in the following order: transformation temperature > induction temperature > IPTG concentration > substrate concentration. The optimal conditions were found to be a transformation temperature of 35 ℃, IPTG concentration of 0.1 mmol·L~(-1), induction temperature of 25 ℃, and substrate concentration of 10 mmol·L~(-1). Finally, the effect of transformation time on the yield of 3,4-DHAP was further examined under the optimal conditions. The results indicated that as the transformation time increased, the yield of 3,4-DHAP steadily increased. The highest yield of 260 mg·L~(-1) with a productivity of 17% was achieved after 72 hours of transformation. In conclusion, this study successfully achieved the whole-cell bioconversion of 1-(4-hydroxyphenol)-ethanol to 3,4-DHAP using recombinant E. coli for the first time, laying the groundwork for further optimization and development of the biosynthesis of 3,4-DHAP.
Escherichia coli/genetics*
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Acetophenones/chemistry*
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Ethanol/chemistry*
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Drugs, Chinese Herbal/chemistry*
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Biotransformation

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