Osteoarthritis (OA), a highly prevalent degenerative joint disease worldwide, is defined by articular cartilage degradation, abnormal bone remodeling, and persistent chronic inflammation. It severely compromises patients’ quality of life, and currently, there is no radical cure. Abnormal mechanical stress is widely regarded as a core driver of OA pathogenesis, and the exploration of mechanical signal perception and transduction mechanisms has become crucial for deciphering OA’s pathophysiological processes. Piezo1, a key mechanosensitive cation channel belonging to the Piezo protein family, has recently gained significant attention due to its pivotal role in mediating cellular responses to mechanical stimuli in joint tissues. This review systematically examines Piezo1’s expression patterns, regulatory mechanisms, and pathological functions in OA, with a particular focus on its dual roles in modulating chondrocyte homeostasis and bone metabolism disorders, while also delving into the underlying molecular signaling pathways and potential therapeutic implications. Piezo1, consisting of approximately 2 500 amino acids and forming a unique trimeric propeller-like structure, is widely expressed in chondrocytes, osteocytes, mesenchymal stem cells, and synovial cells. It exhibits permeability to cations such as Ca²⁺, K⁺, and Na⁺, and directly responds to membrane tension changes induced by mechanical stimuli like fluid shear stress and mechanical overload. In OA patients and animal models, Piezo1 expression is significantly upregulated, especially in cartilage regions subjected to abnormal mechanical stress (e.g., human temporomandibular joint cartilage). This overexpression is closely associated with aggravated cartilage degeneration, increased chondrocyte apoptosis, accelerated cellular senescence, and intensified inflammatory responses. Mechanical overload and pro-inflammatory cytokines (e.g., IL-1β) are key inducers of Piezo1 upregulation: IL-1β activates the PI3K/AKT/mTOR signaling pathway to enhance Piezo1 expression, forming a pathogenic positive feedback loop that inhibits chondrocyte autophagy, promotes apoptosis, and further accelerates joint degeneration. Mechanistically, Piezo1 mediates OA progression through multiple interconnected pathways. When activated by mechanical stress, Piezo1 triggers excessive Ca²⁺ influx, leading to endoplasmic reticulum stress (ERS) and mitochondrial dysfunction, which directly induce chondrocyte apoptosis. This process involves the activation of downstream signaling cascades such as cGAS-STING and YAP-MMP13/ADAMTS5. YAP, a transcriptional regulator, upregulates the expression of matrix metalloproteinase 13 (MMP13) and aggrecanase (ADAMTS5), thereby accelerating cartilage matrix degradation. Additionally, Piezo1-driven Ca²⁺ overload promotes the accumulation of reactive oxygen species (ROS) and upregulates senescence markers (p16 and p21), accelerating chondrocyte senescence via the p38MAPK and NF-κB pathways. Senescent chondrocytes secrete senescence-associated secretory phenotype (SASP) factors (e.g., IL-6, IL-1β), further amplifying joint inflammation. In terms of bone metabolism, Piezo1 maintains joint homeostasis by promoting the differentiation of fibrocartilage stem cells into chondrocytes and balancing bone formation and resorption through regulating the FoxC1/YAP axis and RANKL/OPG ratio. Therapeutically, targeting Piezo1 shows promising potential. Preclinical studies have demonstrated that Piezo1 inhibitors (e.g., GsMTx4) can reduce joint damage and alleviate pain in OA mice. Simultaneously, siRNA-mediated co-silencing of Piezo1 and TRPV4 (another mechanosensitive channel) decreases intracellular Ca²⁺ concentration, inhibits chondrocyte apoptosis, and promotes cartilage repair. Conditional knockout of Piezo1 using Gdf5-Cre transgenic mice alleviates cartilage degeneration in post-traumatic OA models by downregulating MMP13 and ADAMTS5 expression. Despite existing challenges, such as off-target effects of inhibitors, inefficient local drug delivery, and interindividual genetic variability, strategies like developing selective Piezo1 antagonists, optimizing targeted nanocarriers, and combining Piezo1-targeted therapy with physical therapy provide viable avenues for clinical translation. The authors propose that Piezo1 serves as a critical therapeutic target for OA, and future research should focus on deciphering its context-dependent regulatory networks, developing tissue-specific intervention strategies, and validating their efficacy and safety in clinical trials to address the unmet medical needs of OA patients.

OBJECTIVE To investigate the therapeutic effect and mechanism of Qiwei dongqingye powder （QDP） on bronchial asthma in mice. METHODS The mice were divided into blank group （normal saline）， model group （normal saline）， dexamethasone group （2 mg/kg）， and QDP low-， medium-， and high-dose groups （200， 400， 800 mg/kg）， with 14 mice in each group. Except for the blank group， mice in all other groups were given ovalbumin via intraperitoneal injection followed by aerosol inhalation to induce a bronchial asthma model. During the modeling process， mice in each group were administered corresponding drug solutions or normal saline intragastrically/intraperitoneally. After the last medication， the number of cells in the bronchoalveolar lavage fluid （BALF） of the mice was observed and counted； the pathological changes of the bronchus and lung tissue were observed； the levels of malondialdehyde （MDA）， nitric oxide （NO）， total superoxide dismutase （T-SOD）， and glutathione peroxidase （GSH-Px） in the lung tissue of the mice were determined， and the level of interleukin-17 （IL-17） in the BALF and serum was determined. Transcriptomics was employed to predict and validate the mechanism of action of QDP against bronchial asthma. RESULTS Compared with the model group， the total cell count， neutrophil count， lymphocyte count， and macrophage counts in the BALF of the QDP high-dose group were all significantly reduced （ P ＜0.05）； the levels of MDA and NO in the lung tissue， and the levels of IL-17 in the BALF and serum were all decreased significantly （ P ＜0.05）； the levels of T-SOD and GSH-Px were significantly increased （ P ＜0.05）； the arrangement of lung tissue cells tended to normalize， with reduced infiltration of inflammatory cells and decreased exfoliation of bronchial simple columnar epithelial cells. The transcriptomic results revealed that the differentially expressed genes were B-cell receptor signaling pathway， nuclear factor κB （NF-κB） signaling pathway， ferroptosis signaling pathway， and others. Further validation revealed that， compared with the model group， the expression levels of NF-κB p65 and chemokine ligand 20， as well as the phosphorylation level of NF-κB inhibitor protein α， were significantly decreased in the lung tissues of the mice in all QDP groups （ P ＜0.05）. Conversely， the protein expression of nuclear factor erythroid 2-related factor 2 （Nrf2） and heme oxygenase 1 （HO-1） were significantly increased （ P ＜0.05）. CONCLUSIONS QDP can effectively alleviate bronchial asthma by inhibiting the NF-κB signaling pathway， activating the Nrf2/HO-1 signaling pathway， regulating oxidative stress， and reducing inflammatory responses.

Objective To establish a HPLC method for determining thimerosal compounds in eye drops. Methods A gradient HPLC system was used in the quantitative analysis of thimerosal compounds on Shiseido MGII C₁₈ column （4.6 mm×250 mm，5 μm）, using 1% triethylamine solution （pH adjusted to 3.0 with phosphate） as mobile phase A, the methanol as mobile phase B, gradient elution, The column temperature was 40 ℃, the detection wavelength was 222 nm, the flow rate was 1 ml/min and the injection volume was 20 µl. Results The established method had good linearity within the concentration range of 4.3-216.7 μg/ml （r>0.999） for thimerosal, with average recoveries was 102.1%, RSD2.7%. Conclusion This method was simple, accurate and highly specific, and could be used for determination of thimerosal compound in eye drops.

BACKGROUND: Generalized pustular psoriasis (GPP), a rare and recurrent autoinflammatory disease, imposes a substantial burden on patients and society. Awareness of GPP in China remains limited. METHODS: This cross-sectional survey, conducted between September 2021 and May 2023 across 14 hospitals in China, included GPP patients of all ages and disease phases. Data collected encompassed demographics, clinical characteristics, economic impact, disease severity, quality of life, and treatment-related complications. Risk factors for GPP recurrence were analyzed. RESULTS: Among 127 patients (female/male ratio = 1.35:1), the mean age of disease onset was 25 years (1st quartile [Q1]-3rd quartile [Q3]: 11-44 years); 29.2% had experienced GPP for more than 10 years. Recurrence occurred in 75.6% of patients, and nearly half reported no identifiable triggers. Younger age at disease onset ( P  = 0.021) and transitioning to plaque psoriasis ( P  = 0.022) were associated with higher recurrence rates. The median diagnostic delay was 8 months (Q1-Q3: 2-41 months), and 32.3% of patients reported misdiagnoses. Comorbidities were present in 53.5% of patients, whereas 51.1% experienced systemic complications during treatment. Depression and anxiety affected 84.5% and 95.6% of patients, respectively. During GPP flares, the median Dermatology Life Quality Index score was 19.0 (Q1-Q3: 13.0-23.5). This score showed significant differences between patients with and without systemic symptoms; it demonstrated correlations with both depression and anxiety scores. Treatment costs caused financial hardship in 55.9% of patients, underscoring the burden associated with GPP. CONCLUSIONS The substantial disease and economic burdens among Chinese GPP patients warrant increased attention. Patients with early onset disease and those transitioning to plaque psoriasis require targeted interventions to mitigate the high recurrence risk.
Humans ; Male ; Female ; Psoriasis/pathology* ; Adult ; Cross-Sectional Studies ; Adolescent ; Child ; Young Adult ; Quality of Life ; Middle Aged ; China/epidemiology* ; Recurrence ; Risk Factors ; Surveys and Questionnaires ; East Asian People

Based on the epidermal growth factor receptor(EGFR)/mitogen-activated protein kinase(MAPK) signaling pathway-mediated cell proliferation, this study explores the effect of cisplatin combined with Guiqi Yiyuan Ointment on Lewis lung cancer-bearing mice. A total of 60 male C57BL/6 mice were randomly divided into a blank group with 10 mice and a modeling group with 50 mice. After modeling, they were randomly divided into the model group, cisplatin group, and low-, medium-, and high-dose groups of cisplatin combined with Guiqi Yiyuan Ointment, with 10 mice in each group. After 14 days of medication, the general condition of the mice was observed; body weight was measured, and organ index and tumor inhibition rate were calculated. Hematoxylin-eosin(HE) staining was used to observe the pathological morphology changes in tumor tissue. Immunohistochemistry was used to detect the positive rate of Ki-67 antigen(Ki-67) and proliferating cell nuclear antigen(PCNA) in tumor tissue. Western blot and real time-quantitative polymerase chain reaction(qPCR) were used to detect the expression of related proteins and mRNA in tumor tissue. Flow cytometry was used to detect the cell cycle of tumor cells in tumor tissue. The results showed that compared with that in the blank group, the general condition of mice in the model group deteriorated; the body weight, as well as thymus and spleen index of mice in the model group decreased after 14 days of medication. Compared with that in the model group, the general condition of mice in the cisplatin group deteriorated, while the condition of mice in the combined groups improved; the body weight, as well as thymus and spleen index of mice in the cisplatin group decreased, while the three indicators in the combined groups increased; the tumor weight of each medication group decreased, and the tumor inhibition rate increased; there were varying degrees of necrosis in tumor cells of each medication group, and the tightness of tumor cells, the increase in the number of cell nuclei and chromatin, and mitosis all decreased. The positive rate of Ki-67 and PCNA, as well as the protein expression and ratio of p-EGFR/EGFR, rat sarcoma viral oncogene homolog(Ras), phosphorylated Raf-1 protein kinase(p-Raf-1)/Raf-1, phosphorylated mitogen-activated protein kinase kinase(p-MEK)/MEK, phosphorylated extracellular signal-regulated kinase(p-ERK)/ERK and the mRNA expression of EGFR, Ras, Raf-1, MEK, and ERK all decreased. The proportion of tumor cells in the G_0/G_1 phase of each medication group increased, and that in the S phase decreased. In addition, there was no significant difference in the G_2/M phase. Compared with that of the cisplatin group, the tumor weight of the combined groups decreased, and the tumor inhibition rate increased. The necrosis and mitosis of tumor cells in the combined groups were more pronounced; the positive rate of Ki-67 and PCNA, the protein expression and ratio of p-EGFR/EGFR, Ras, p-Raf-1/Raf-1, p-MEK/MEK, and p-ERK/ERK, as well as the mRNA expression of EGFR, Ras, Raf-1, MEK, and ERK in the combined groups all decreased. The proportion of tumor cells in the G_0/G_1 phase of the combined medium-and high-dose groups increased, and that in the S phase decreased. There was no significant difference in the proportion of tumor cells of the combined groups in the G_2/M phase. This indicates that the combination of cisplatin and Guiqi Yiyuan Ointment can enhance the anti-tumor effect of cisplatin on tumor-bearing mice, and the mechanism may be associated with the inhibition of the EGFR/MAPK pathway, which accelerates the arrest of tumor cells in the G_0/G_1 phase, thereby inhibiting the proliferation of tumor cells. At the same time, the study also indicates that Guiqi Yiyuan Ointment may reduce the damage of tumors to mice and the toxic side effects brought by cisplatin chemotherapy.
Animals ; Male ; Carcinoma, Lewis Lung/metabolism* ; Drugs, Chinese Herbal/administration & dosage* ; ErbB Receptors/genetics* ; Mice ; Cisplatin/administration & dosage* ; Mice, Inbred C57BL ; Cell Proliferation/drug effects* ; Ointments/administration & dosage* ; MAP Kinase Signaling System/drug effects* ; Humans ; Antineoplastic Agents/administration & dosage* ; Lung Neoplasms/metabolism*

This study predicts the quality markers(Q-markers) for the cough-relieving and phlegm-expelling effects of Kening Granules based on pharmacodynamics, plasma drug chemistry, network pharmacology, and pharmacokinetics. Strong ammonia solution spray and phenol red secretion assays were employed to evaluate the cough-relieving and phlegm-expelling effects of Kening Granules. Twentysix absorbed prototype components of Kening Granules were identified by ultra high performance liquid chromatography coupled with QExactive Plus quadrupole/Orbitrap high resolution mass spectrometry(UHPLC-Q-Exactive Plus Orbitrap HRMS). Through network pharmacology, 11 potential active components were screened out for the cough-relieving and phlegm-expelling effects of Kening Granules. The 11 components acted on 40 common targets such as IL6, TLR4, and STAT3, which mainly participated in PI3K/Akt, HIF-1, and EGFR signaling pathways. Pharmacokinetic quantitative analysis was performed for 7 prototype components. Three compounds including azelaic acid, caffeic acid, and vanillin were identified as Q-markers for the cough-relieving and phlegm-expelling effects of Kening Granules based on their effectiveness, transmissibility, and measurability. The results of this study are of great significance for clarifying the pharmacological substance basis, optimizing the quality standards, and promoting the clinical application of Kening Granules.
Drugs, Chinese Herbal/administration & dosage* ; Network Pharmacology ; Cough/blood* ; Male ; Humans ; Animals ; Rats ; Rats, Sprague-Dawley ; Biomarkers/blood* ; Quality Control ; Chromatography, High Pressure Liquid ; Antitussive Agents/chemistry*

Polygonati Rhizoma demonstrates significant potential for addressing both chronic and hidden hunger. The supply of high-quality seedlings is a primary factor influencing the development of the Polygonati Rhizoma industry. Warm water soaking is often used in agriculture to promote the rapid germination of seeds, while its application and molecular mechanism in Polygonati Rhizoma have not been reported. To rapidly obtain high-quality seedlings, this study treated Polygonatum kingianum var. grandifolium seeds with sand storage at low temperatures, warm water soaking, and cultivation temperature gradients. The results showed that the culture at 25 ℃ or sand storage at 4 ℃ for 2 months rapidly broke the seed dormancy of P. kingianum var. grandifolium, while the culture at 20 ℃ or sand storage at 4 ℃ for 1 month failed to break the seed dormancy. Soaking seeds in 60 ℃ warm water further increased the germination rate, germination potential, and germination index. Specifically, the seeds soaked at 60 ℃ and cultured at 25 ℃ without sand storage treatment(Aa25) achieved a germination rate of 78. 67%±1. 53% on day 42 and 83. 40%±4. 63% on day 77. The seeds pretreated with sand storage at 4 ℃ for 2 months, soaked in 60 ℃ water, and then cultured at 25 ℃ achieved a germination rate comparable to that of Aa25 on day 77. Transcriptomic analysis indicated that warm water soaking might promote germination by triggering reactive oxygen species( ROS), inducing the expression of heat shock factors( HSFs) and heat shock proteins( HSPs), which accelerated DNA replication, transcript maturation, translation, and processing, thereby facilitating the accumulation and turnover of genetic materials. According to the results of indoor controlled experiments and field practices, maintaining a germination and seedling cultivation environment at approximately 25 ℃ was crucial for the one-year seedling cultivation of P. kingianum var. grandifolium.
Germination ; Seedlings/genetics* ; Water/metabolism* ; Seeds/metabolism* ; Polygonatum/genetics* ; Temperature ; Plant Proteins/genetics* ; Plant Dormancy

This study aims to investigate the anti-tumor effect and mechanism of Guiqi Yiyuan Ointment combined with cisplatin on Lewis lung carcinoma-bearing mice via the protein kinase RNA-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2α(eIF2α)/activated transcription factor 4(ATF4)/C/EBP homologous protein(CHOP) signaling pathway. Sixty SPF-grade male C57BL/6 mice were selected and assigned into a blank group and a modeling group by the random number table method. After modeling of the Lewis lung carcinoma, the mice in the modeling group were randomized into model, cisplatin(5 mg·kg~(-1), once a week), and low-, medium-, and high-dose(1.7, 3.5, and 7.05 g·kg~(-1), respectively, once a day) Guiqi Yiyuan Ointment+cisplatin(5 mg·kg~(-1)) groups(n=10). After 14 days of continuous intervention, the spleen, thymus, and tumor samples of the mice were collected, weighed, and recorded, and the spleen index, thymus index, and tumor suppression rate were calculated. Hematoxylin-eosin(HE) staining was employed to observe the pathological changes in the tumor tissue. The morphological changes of the endoplasmic reticulum of tumor cells were observed by transmission electron microscopy. The positive expression of phosphorylated eIF2α(p-eIF2α) and ATF4 in the tumor tissue was detected by immunofluorescence. Western blot was employed to determine the protein levels of phosphorylated PERK(p-PERK), p-eIF2α, ATF4, CHOP, B-cell lymphoma-2(Bcl-2), Bcl-2-associated X protein(Bax), cyclin-dependent kinase inhibitor 1A(p21), and cyclinD1 in the tumor tissue. Real-time fluorescent quantitative PCR was employed to determine the mRNA levels of PERK, eIF2α, ATF4, CHOP, Bax, Bcl-2, p21, and cyclinD1 in the tumor tissue. Compared with the blank group, the model group showed decreases in spleen index and thymus index(P<0.05). Compared with the model group, the cisplatin group showed decreases in spleen index and thymus index(P<0.05), and the medium-and high-dose Guiqi Yiyuan Ointment+cisplatin groups presented increases in spleen index and thymus index(P<0.05). In addition, the treatment groups all showed decreased tumor mass(P<0.05), increased tumor cell lysis and nuclear rupture, widened gap between rough endoplasmic reticulum, enhanced average fluorescence intensity of p-eIF2α and ATF4(P<0.05), up-regulated protein levels of p-PERK/PERK, p-eIF2α/eIF2α, ATF4, CHOP, Bax, and p21(P<0.05), down-regulated protein and mRNA levels of Bcl-2 and cyclinD1(P<0.05), and up-regulated mRNA levels of PERK, eIF2α, ATF4, CHOP, Bax, and p21(P<0.05). Compared with the cisplatin group, the combination groups showed increases in spleen index and thymus index(P<0.05) as well as mean optical density(P<0.05), and the high-dose Guiqi Yiyuan Ointment+cisplatin group showed decreased tumor mass(P<0.05). In addition, the medium-and high-dose Guiqi Yiyuan Ointment+cisplatin groups showcased enhanced average fluorescence intensity of p-eIF2α and ATF4(P<0.05), up-regulated protein levels of p-PERK/PERK, p-eIF2α/eIF2α, ATF4, CHOP, Bax, and p21(P<0.05), down-regulated protein and mRNA levels of Bcl-2 and cyclinD1(P<0.05), and up-regulated mRNA levels of PERK, eIF2α, ATF4, CHOP, Bax, and p21(P<0.05). In conclusion, Guiqi Yiyuan Ointment combined with cisplatin can effectively inhibit the growth of Lewis lung carcinoma in mice by regulating the expression of proteins related to the PERK/eIF2α/ATF4/CHOP signaling pathway and promoting cell cycle arrest and apoptosis.
Animals ; Cisplatin/administration & dosage* ; Activating Transcription Factor 4/genetics* ; Eukaryotic Initiation Factor-2/genetics* ; eIF-2 Kinase/genetics* ; Carcinoma, Lewis Lung/pathology* ; Drugs, Chinese Herbal/administration & dosage* ; Male ; Mice ; Signal Transduction/drug effects* ; Mice, Inbred C57BL ; Transcription Factor CHOP/genetics* ; Ointments/administration & dosage* ; Humans ; Cell Proliferation/drug effects* ; Antineoplastic Agents/administration & dosage*

This study aims to investigate the potential effect of the water extract of fresh Rehmanniae Radix on hypercholesterolemia in mice that was induced by a high-fat and high-cholesterol diet and explore its possible mechanism from bile acid reabsorption. Male C57BL/6 mice were randomly assigned into the following groups: control, model, low-and high-dose(4 and 8 g·kg~(-1), respectively) fresh Rehmanniae Radix, and positive drug(simvastatin, 0.05 g·kg~(-1)). Other groups except the control group were fed with a high-fat and high-cholesterol diet for 6 consecutive weeks to induce hypercholesterolemia. From the 6th week, mice were administrated with corresponding drugs daily via gavage for additional 6 weeks, while continuing to be fed with a high-fat and high-cholesterol diet. Serum levels of total cholesterol(TC), triglycerides(TG), low density lipoprotein-cholesterol(LDL-c), high density lipoprotein-cholesterol(HDL-c), and total bile acid(TBA), as well as liver TC and TG levels and fecal TBA level, were determined by commercial assay kits. Hematoxylin-eosin(HE) staining, oil red O staining, and transmission electron microscopy were performed to observe the pathological changes in the liver. Three livers samples were randomly selected from each of the control, model, and high-dose fresh Rehmanniae Radix groups for high-throughput transcriptome sequencing. Differentially expressed genes were mined and KEGG pathway enrichment analysis was performed to predict the key pathways and target genes of the water extract of fresh Rehmanniae Radix in the treatment of hypercholesterolemia. RT-qPCR was employed to measure the mRNA levels of cholesterol 7α-hydroxylase(CYP7A1) and cholesterol 27α-hydroxylase(CYP27A1) in the liver. Western blot was employed to determine the protein levels of CYP7A1 and CYP27A1 in the liver as well as farnesoid X receptor(FXR), apical sodium-dependent bile acid transporter(ASBT), and ileum bile acid-binding protein(I-BABP) in the ileum. The results showed that the water extract of fresh Rehmanniae Radix significantly lowered the levels of TC and TG in the serum and liver, as well as the level of LDL-c in the serum. Conversely, it elevated the level of HDL-c in the serum and TBA in feces. No significant difference was observed in the level of TBA in the serum among groups. HE staining, oil red O staining, and transmission electron microscopy showed that the water extract reduced the accumulation of lipid droplets in the liver. Further mechanism studies revealed that the water extract of fresh Rehmanniae Radix significantly down-regulated the protein levels of FXR and bile acid reabsorption-related proteins ASBT and I-BABP. Additionally, it enhanced CYP7A1 and CYP27A1, the key enzymes involved in bile acid synthesis. Therefore, it is hypothesized that the water extract of fresh Rehmanniae Radix may exert an anti-hypercholesterolemic effect by regulating FXR/ASBT/I-BABP signaling, inhibiting bile acid reabsorption, and increasing bile acid excretion, thus facilitating the conversion of cholesterol to bile acids.
Animals ; Male ; Bile Acids and Salts/metabolism* ; Mice, Inbred C57BL ; Mice ; Diet, High-Fat/adverse effects* ; Cholesterol/metabolism* ; Drugs, Chinese Herbal/administration & dosage* ; Hypercholesterolemia/genetics* ; Receptors, Cytoplasmic and Nuclear/genetics* ; Rehmannia/chemistry* ; Liver/drug effects* ; Humans ; Cholesterol 7-alpha-Hydroxylase/genetics* ; Plant Extracts

Panax species are mostly valuable medicinal plants. While some species' seeds are sensitive to dehydration, the dehydration tolerance of seeds from other Panax species remains unclear. The phospholipase D(PLD) gene plays an important role in plant responses to dehydration stress. However, the characteristics of the PLD gene family and their mechanisms of response to dehydration stress in seeds of Panax species with different dehydration tolerances are not well understood. This study used seeds from eight Panax species to measure the germination rates and PLD activity after dehydration and to analyze the correlation between dehydration tolerance and seed traits. Bioinformatics analysis was also conducted to characterize the PnPLD and PvPLD gene families and to evaluate their expression patterns under dehydration stress. The dehydration tolerance of Panax seeds was ranked from high to low as follows: P. ginseng, P. zingiberensis, P. quinquefolius, P. vietnamensis var. fuscidiscus, P. japonicus var. angustifolius, P. japonicus, P. notoginseng, and P. stipuleanatus. A significant negative correlation was found between dehydration tolerance and seed shape(three-dimensional variance), with flatter seeds exhibiting stronger dehydration tolerance(r=-0.792). Eighteen and nineteen PLD members were identified in P. notoginseng and P. vietnamensis var. fuscidiscus, respectively. These members were classified into five isoforms: α, β, γ, δ, and ζ. The gene structures, subcellular localization, physicochemical properties, and other characteristics of PnPLD and PvPLD were similar. Both promoters contained regulatory elements associated with plant growth and development, hormone responses, and both abiotic and biotic stress. During dehydration, the PLD enzyme activity in P. notoginseng seeds gradually increased as the water content decreased, whereas in P. vietnamensis var. fuscidiscus, PLD activity first decreased and then increased. The expression of PLDα and PLDδ in P. notoginseng seeds initially increased and then decreased, whereas in P. vietnamensis var. fuscidiscus, the expression of PLDα and PLDδ consistently decreased. In conclusion, the dehydration tolerance of Panax seeds showed a significant negative correlation with seed shape. The dehydration tolerance in P. vietnamensis var. fuscidiscus and dehydration sensitivity of P. notoginseng seeds may be related to differences in PLD enzyme activity and the expression of PLDα and PLDδ genes. This study provided the first systematic comparison of dehydration tolerance in Panax seeds and analyzed the causes of tolerance differences and the optimal water content for long-term storage at ultra-low temperatures, thus providing a theoretical basis for the short-term and ultra-low temperature long-term storage of medicinal plant seeds with varying dehydration tolerances.
Seeds/metabolism* ; Panax/physiology* ; Plant Proteins/metabolism* ; Gene Expression Regulation, Plant ; Phospholipase D/metabolism* ; Plants, Medicinal/enzymology* ; Germination ; Multigene Family ; Water/metabolism* ; Dehydration ; Phylogeny