1.Applications of Lactoferrin and Its Nanoparticles in Cancer Therapy
Wen-Tian YUE ; Shu-Rong HE ; Qin AN ; Yun-Xia ZOU ; Wen-Wen DONG ; Qing-Yong MENG ; Ya-Li ZHANG
Progress in Biochemistry and Biophysics 2026;53(2):342-355
Cancer remains a leading cause of global mortality, necessitating the development of advanced therapeutic strategies with enhanced efficacy and reduced systemic toxicity. Among promising bioactive agents, lactoferrin (LF)—a multifunctional iron-binding glycoprotein abundantly found in mammalian milk and exocrine secretions—has garnered significant interest for its potent and multifaceted anti-cancer properties. This review provides a comprehensive analysis of the current understanding of LF’s role in oncology, encompassing its structural biology, diverse mechanisms of action, and groundbreaking advancements in its application through nano-engineering. LF exerts anti-tumor effects through multiple pathways, including extracellular action, intracellular action, and immune regulation. It demonstrates a remarkable affinity for cancer cell membranes, binding to overexpressed anionic components such as glycosaminoglycans and sialic acids, as well as to specific receptors including the low-density lipoprotein receptor-related protein-1 (LRP-1). This selective binding facilitates targeted uptake. Upon internalization, LF orchestrates a direct assault by inducing cell-cycle arrest in phases such as G0/G1 or S phase through the modulation of key regulators including cyclins, CDKs, and p53. Furthermore, it promotes programmed cell death via apoptotic pathways, involving caspase activation and downregulation of anti-apoptotic proteins such as survivin. A more recently elucidated mechanism is the induction of ferroptosis, an iron-dependent form of cell death characterized by overwhelming lipid peroxidation. Beyond direct cytotoxicity, LF acts as a potent immunomodulator. It enhances natural killer (NK) cell activity, modulates T-lymphocyte populations, and crucially reprograms tumor-associated macrophages (TAMs) from a pro-tumor M2 state to an anti-tumor M1 state, thereby reversing the immunosuppressive tumor microenvironment (TME). The translation of LF’s potential has been significantly accelerated by nanotechnology. The inherent biocompatibility and natural tumor-targeting capabilities of LF make it an ideal platform for sophisticated drug-delivery systems. This review details various fabrication strategies for LF-based nanoparticles (NPs), including self-assembly, sol-in-oil emulsion, and electrostatic nanocomplexes, among others. Research demonstrates that nano-formulations not only protect LF from degradation but also enhance its bioactivity and anti-cancer potency. More importantly, LF NPs serve as versatile carriers for a wide array of therapeutic agents, including conventional chemotherapeutics, natural compounds, and imaging agents. These engineered systems enable synergistic therapy and facilitate site-specific delivery. Notably, the ability of LF to bind to receptors on the blood-brain barrier (BBB) has been leveraged to develop nano-systems for glioblastoma treatment. Other innovative designs utilize LF to modulate the TME—for instance, by alleviating tumor hypoxia to sensitize cells to radiotherapy and chemotherapy. Despite compelling pre-clinical evidence, the clinical translation of LF and its nano-formulations remains nascent. While early-phase trials have established a favorable safety profile for recombinant human LF, larger Phase III studies have yielded mixed results, underscoring the complexity of its action in humans. Key challenges include enhancing drug targeting, optimizing loading efficiency, ensuring batch-to-batch reproducibility, and achieving deep tumor penetration. Future research must focus on the rational design of next-generation LF-NPs. This entails developing standardized manufacturing protocols, engineering “smart” stimuli-responsive systems for targeted drug release in the TME, and constructing multi-targeting platforms. A concerted interdisciplinary effort is paramount to bridge the gap between bench and bedside. In conclusion, LF, particularly in its nano-engineered forms, represents a highly promising and versatile agent in the oncological arsenal, holding immense potential for precise and effective cancer therapy.
2.Applications of Lactoferrin and Its Nanoparticles in Cancer Therapy
Wen-Tian YUE ; Shu-Rong HE ; Qin AN ; Yun-Xia ZOU ; Wen-Wen DONG ; Qing-Yong MENG ; Ya-Li ZHANG
Progress in Biochemistry and Biophysics 2026;53(2):342-355
Cancer remains a leading cause of global mortality, necessitating the development of advanced therapeutic strategies with enhanced efficacy and reduced systemic toxicity. Among promising bioactive agents, lactoferrin (LF)—a multifunctional iron-binding glycoprotein abundantly found in mammalian milk and exocrine secretions—has garnered significant interest for its potent and multifaceted anti-cancer properties. This review provides a comprehensive analysis of the current understanding of LF’s role in oncology, encompassing its structural biology, diverse mechanisms of action, and groundbreaking advancements in its application through nano-engineering. LF exerts anti-tumor effects through multiple pathways, including extracellular action, intracellular action, and immune regulation. It demonstrates a remarkable affinity for cancer cell membranes, binding to overexpressed anionic components such as glycosaminoglycans and sialic acids, as well as to specific receptors including the low-density lipoprotein receptor-related protein-1 (LRP-1). This selective binding facilitates targeted uptake. Upon internalization, LF orchestrates a direct assault by inducing cell-cycle arrest in phases such as G0/G1 or S phase through the modulation of key regulators including cyclins, CDKs, and p53. Furthermore, it promotes programmed cell death via apoptotic pathways, involving caspase activation and downregulation of anti-apoptotic proteins such as survivin. A more recently elucidated mechanism is the induction of ferroptosis, an iron-dependent form of cell death characterized by overwhelming lipid peroxidation. Beyond direct cytotoxicity, LF acts as a potent immunomodulator. It enhances natural killer (NK) cell activity, modulates T-lymphocyte populations, and crucially reprograms tumor-associated macrophages (TAMs) from a pro-tumor M2 state to an anti-tumor M1 state, thereby reversing the immunosuppressive tumor microenvironment (TME). The translation of LF’s potential has been significantly accelerated by nanotechnology. The inherent biocompatibility and natural tumor-targeting capabilities of LF make it an ideal platform for sophisticated drug-delivery systems. This review details various fabrication strategies for LF-based nanoparticles (NPs), including self-assembly, sol-in-oil emulsion, and electrostatic nanocomplexes, among others. Research demonstrates that nano-formulations not only protect LF from degradation but also enhance its bioactivity and anti-cancer potency. More importantly, LF NPs serve as versatile carriers for a wide array of therapeutic agents, including conventional chemotherapeutics, natural compounds, and imaging agents. These engineered systems enable synergistic therapy and facilitate site-specific delivery. Notably, the ability of LF to bind to receptors on the blood-brain barrier (BBB) has been leveraged to develop nano-systems for glioblastoma treatment. Other innovative designs utilize LF to modulate the TME—for instance, by alleviating tumor hypoxia to sensitize cells to radiotherapy and chemotherapy. Despite compelling pre-clinical evidence, the clinical translation of LF and its nano-formulations remains nascent. While early-phase trials have established a favorable safety profile for recombinant human LF, larger Phase III studies have yielded mixed results, underscoring the complexity of its action in humans. Key challenges include enhancing drug targeting, optimizing loading efficiency, ensuring batch-to-batch reproducibility, and achieving deep tumor penetration. Future research must focus on the rational design of next-generation LF-NPs. This entails developing standardized manufacturing protocols, engineering “smart” stimuli-responsive systems for targeted drug release in the TME, and constructing multi-targeting platforms. A concerted interdisciplinary effort is paramount to bridge the gap between bench and bedside. In conclusion, LF, particularly in its nano-engineered forms, represents a highly promising and versatile agent in the oncological arsenal, holding immense potential for precise and effective cancer therapy.
3.Sequence analysis of variable regions of human monoclonal anti-P immunoglobulin
Zhonghui GUO ; Dong XIANG ; Qin LI ; Ziyan ZHU
Chinese Journal of Blood Transfusion 2026;39(1):24-30
Objective: To identify the structure of the complementarity determining region (CDRs), the V(D)J rearrangement and somatic hypermutational characteristics of the heavy and light chains of a red blood cell blood group-specific monoclonal antibody. Methods: The hybridoma cell line secreting human IgM κ monoclonal anti-P antibody was used as the research object. Total RNA was extracted from cultured monoclonal cell line, and cDNA was obtained by reverse transcription PCR (RT-PCR) using random hexamers primers. It was then amplified and sequenced using primers specific for variable regions of the immunoglobulin heavy and light chains encoding the anti-P antibody. The sequences were aligned against the NCBI database using online Immunoglobulin BLAST (Ig-BLAST) tool. Results: The study determined the structure of the CDRs and framework regions (FRs) of the variable regions of human monoclonal anti-P immunoglobulin, as well as the characteristics of V(D)J rearrangement. Moreover, the closest VH, VD, and VJ germline alleles for the heavy chain and VL and VJ germline alleles for the light chain were also identified. The IgH gene rearrangment pattern of the monoclonal anti-P was IGHV6-1
* 01—IGHD5-18
02—IGHJ4
02 and IgL gene was IGκV1-12
01—IGκJ3
01. Nine base mutations occurred within the germline gene IGHV6-1
01 in variable region of heavy chain, whereas 5 base mutations were found in the germline gene IGκV1-12
01 in variable region of light chain, respectively. Conclusion: This study characterized the CDR structure in monoclonal antibody cell line targeting the high-frequency red blood cell P antigen, and provided a foundation for the construction of recombinant antibody expressing plasmids and transfomation of the immunoglobulin type.
4.Predictive model for severe adverse reaction associated with bevacizumab based on the global trigger tool and machine learning
Yongfei FU ; Xin LONG ; Hongzhen XU ; Jian TANG ; Xiangqing LI ; Yucheng LONG ; Dong QIN
China Pharmacy 2026;37(4):497-503
OBJECTIVE To confirm trigger items for adverse drug reaction (ADR) induced by bevacizumab, to identify and analyze the occurrence of related ADR, and to establish a predictive model for severe adverse reaction (SAR) caused by this drug. METHODS Based on the global trigger tool (GTT) theory, and referencing the GTT White Paper, drug package inserts and relevant literature, trigger items for bevacizumab-related ADR were confirmed using a single-round Delphi method. Utilizing these established items, electronic medical records of relevant patients at Guilin People’s Hospital from January 2020 to September 2024 were actively screened via the China Hospital Pharmacovigilance System. Pharmacists then identified and tallied the occurrence of bevacizumab-induced ADR. Data from patients with any positive trigger item served as the study subjects (divided into training and test sets at a ratio of 7∶3), candidate feature variables were selected from 39 related variables using the Boruta algorithm, and the multivariable Logistic regression analysis was performed with the occurrence of SAR as the dependent variable. Based on these candidate features, Logistic Regression, Extreme Gradient Boosting, Light Gradient Boosting Machine, Random Forest, and Categorical Boosting models were constructed. Model performance was evaluated using metrics including the area under the curve (AUC) of receiver operating characteristic curve and recall rate. The Shapley Additive exPlanations (SHAP) method was applied to analyze and interpret the contribution of each variable. A nomogram was constructed based on the optimal model. RESULTS A total of 38 trigger items for active monitoring of bevacizumab-related ADR were determined, comprising 17 laboratory indicators, 13 clinical manifestations, and 8 intervention measures. In total, 483 patients with positive trigger items were included, and 318 patients with bevacizumab-induced ADR were identified, including 83 SARs. The positive predictive values for the trigger items and cases were 43.57% (708/1 625) and 63.84% (318/483), respectively. Bevacizumab-induced ADR involved 7 systems/organs, with the hematological system being the most frequently involved (64.15%). The Boruta algorithm selected 7 vari ables: serum potassium, hematocrit, albumin-to-globulin ratio, prealbumin, hypertension history, age and red blood cell count. Multivariable Logistic regression showed that elevated serum potassium levels were associated with a decreased risk of bevacizumab-induced SAR (OR=0.234, P =0.002), while a history of hypertension (OR=2.642, P =0.006) and increased age (OR=1.040, P =0.025) were associated with an increased risk. The Logistic Regression model demonstrated superior performance with higher AUC, F1 score and recall rate (0.761, 0.447, 0.607), compared to other models. SHAP evaluation results indicated that variables such as serum potassium, hematocrit, and age ranked highest in importance. CONCLUSIONS Totally 38 trigger entries have been successfully identified for active screening of bevacizumab-related ADR. Elevated serum potassium levels are a protective factor against bevacizumab-induced SAR, whereas the hypertension history and increased age are risk factors. The Logistic Regression model is the optimal predictive model.
5.Evaluation of CARIFS Score and Negative Antigen Conversion Rate of Qingxuan Daozhi Formula in Treatment of Influenza in Children (Heat Accumulation in Lung and Stomach Syndrome):A Multi-center Randomized Controlled Clinical Study
Jing WANG ; Liqun WU ; Tiegang LIU ; Yongning CAO ; Jing QIU ; Jing LI ; Huaqing TAN ; Ying ZHANG ; Xulei GOU ; Jia WANG ; Jing LI ; Haipeng CHEN ; Xueying QIN ; Yuanshuo TIAN ; Yang WANG ; Chen BAI ; Zhendong WANG ; Qianqian LI ; He YU ; Xueyan MA ; Fei DONG ; Lin JIANG ; Yingqi XU ; Jianping LIU ; Xiaohong GU
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(13):188-196
ObjectiveThis paper aims to observe the syndrome improvement and negative antigen conversion rate of Qingxuan Daozhi formula in the treatment of influenza in children (heat accumulation in the lung and stomach syndrome). MethodsThrough a multi-center randomized controlled methodology design,confirmed influenza cases were collected from October 2022 to April 2023 in the pediatrics department of eight hospitals,such as Dongfang Hospital of Beijing University of Chinese Medicine. A total of 180 children with influenza and heat accumulation in the lung and stomach syndrome conforming to the standard were recruited through the clinic. The sick children meeting the inclusion criteria were randomly divided into groups by a block-randomized method. The children in the experimental group were treated with Qingxuan Daozhi formula for five days,and those in the control group were treated with Oseltamivir Phosphate Granules for five days. The primary efficacy indicator was the negative conversion rate of influenza antigen detection. Secondary efficacy indicators were the Canadian acute respiratory illness and flu scale (CARIFS) and the incidence of complications,severe cases, and critical cases. Follow-up observation was conducted on the day of enrollment,48 hours after medication,72 hours after medication, and (6+1) d after medication. ResultsOne hundred and eighty participants were randomly assigned to the experimental group (90 cases) or the control group (90 cases). All participants were followed up during the study. Comparison of influenza antigen detection results in the primary efficacy indicators showed that the average time of negative influenza antigen conversion in the experimental group was (5.29±1.25) d,and that in the control group was (5.40±1.68) d,without a statistically significant difference. After five days of intervention,52 cases in the experimental group and 51 cases in the control group converted to negative,without a statistically significant difference. CARIFS score results in the secondary efficacy indicators showed that during 72 hours after intervention,there were statistically significant differences between the experimental group and the control group in three dimensions, including headache,muscle soreness, and the need for extra care (P<0.05). On the (6+1) days after the intervention,the differences in both the experimental group and the control group were statistically significant in 10 dimensions, including sore throat,bad sleep,uncomfortable feeling,poor spirit and fatigue,crying more than usual,the need for extra care,symptom,function,influence on parents,and total score (P<0.05). The comparison results within the group in the dimensional scores of symptom, function, and influence on parents,as well as the CARIFS total score showed that with the delay of follow-up time,scores of both groups decreased significantly,with a statistically significant difference (P<0.01). Inter-group comparison results showed that the mean score of the experimental group was higher than that of the control group at the time of enrollment. With the progress of intervention,the score of the experimental group was significantly decreased compared with that of the control group. At the end of follow-up,the mean score of the experimental group was lower than that of the control group,with no statistically significant difference. In terms of the incidence of complications,severe cases, and critical cases, there were no complications,severe cases, and critical cases in the two groups,without a statistically significant difference. ConclusionThe symptom improvement effect and negative antigen conversion rate of Qingxuan Daozhi formula in the treatment of influenza in children (heat accumulation in the lung and stomach syndrome) are not inferior to Oseltamivir Phosphate granules, and children's acceptance is better. It can be more widely used in clinical treatment of influenza in children (heat accumulation in the lung and stomach syndrome).
6.Efficacy of 0.05% cyclosporine combined with olopatadine hydrochlorideeye drops for moderate-to-severe pediatric vernal keratoconjunctivitis
Jingwei LI ; Lan YU ; Qiaoqiao DONG ; Jiao QIN
International Eye Science 2026;26(9):1661-1664
AIM:To observe the therapeutic efficacy of 0.05% cyclosporine combined with olopatadine hydrochlorideeye drops in the treatment of moderate-to-severe pediatric vernal keratoconjunctivitis.METHODS:A prospective randomized controlled study was conducted. Patients with moderate-to-severe pediatric vernal keratoconjunctivitis admitted to the hospital from January to December 2023 were collected and divided into two groups according to the random number table method: the observation group was treated with olopatadine combined with 0.05% cyclosporine hydrochloride eye drops [1 drop per time of 0.05% cyclosporine eye drops(II), four times a day; 1 drop per time of olopatadine hydrochloric eye drops, twice a day]; the control group was treated with sodium hyaluronate combined with olopatadine hydrochloride eye drops(1 drop per time of sodium hyaluronate eye drops, four times a day; 1 drop per time of olopatadine hydrochloric eye drops, twice a day; ). The treatment lasted for 12 wk. The changes in symptom and sign scores of the two groups before treatment, and at 4, 8, and 12 wk after treatment were compared.RESULTS:Totally 42 children(84 eyes)with moderate-to-severe vernal keratoconjunctivitis were enrolled. All patients returned for follow-up visits on time, with no lossto follow-up. The observation group consisted of 21 patients(42 eyes), with 15 males and 6 females, and the average age was 9.00±3.02 y. The control group consisted of 21 patients(42 eyes), with 18 males and 3 females, and the average age was 9.38±3.28 y(all P>0.05). At 4, 8, and 12 wk after treatment, the ocular symptom and sign scores of both groups decreased compared to those before treatment(all P<0.05), and the decrease in the observation group was more significant than that in the control group(P<0.05). During the treatment period, one patient in the observation group experienced a transient mild ocular irritation at the beginning of medication, which was not treated specially and relieved spontaneously after 3 d. No severe adverse reactions such as elevated intraocular pressure or corneal infection occurred in either group during the treatment period.CONCLUSION:The combination of 0.05% cyclosporine and olopatadine hydrochlorideeye drops significantly alleviates the clinical symptoms and signs of moderate-to-severe vernal keratoconjunctivitis, showing favorable safety and efficacy in the treatment of moderate-to-severe pediatric vernal keratoconjunctivitis.
7.Toxic Mechanism, Risk Evaluation, and Regulatory Policies of Pyrrolizidine Alkaloids from Senecionis Scandentis Herba: A Review
Weili CHEN ; Shengxuan LI ; Linying QIN ; Xiangle MENG ; Yu DONG ; Long CHENG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(21):330-338
ObjectiveTo summarize the research results on the toxic mechanism and the relevant regulatory policies at home and abroad of pyrrolizidine alkaloids (PAs), the main toxic components, in Senecionis Scandentis Herba, thereby providing insights into the clinical use and scientific regulation of Senecionis Scandentis Herba. MethodsMultiple Chinese and English databases including PubMed, ScienceDirect, Elsevier, China national knowledge infrastructure (CNKI), Wanfang Data, and VIP were searched, with "Senecio," "PSenecio scandens," and "pyrrolizidine alkaloids" as search terms. The relevant articles published from 1959 to 2025 were retrieved and analyzed, and 79 articles were finally selected for review. ResultsThe chemical components of Senecionis Scandentis Herba include alkaloids, flavonoids, volatile oils, sesquiterpenes, jacaranone derivatives, and organic acids, among which alkaloids are the most toxic components, followed by jacaranone derivatives. PAs are metabolized into highly active pyrrole derivatives in the liver, which can cause serious adverse reactions such as sinusoidal obstruction syndrome and DNA damage. The content of PAs varies significantly due to the origin, harvest period, and medicinal parts. There have been reports of clinical liver injury caused by preparations containing Senecionis Scandentis Herba, and some preparations have a daily intake of PAs exceeding the international safety threshold. Currently, international organizations have set limited standards for PAs, while China only controls the content of adonifoline, and the supervision is not yet perfect. ConclusionAlthough Senecionis Scandentis Herba has medicinal value, its PAs have significant toxicological properties. This is a problem that cannot be ignored and needs to be overcome in the use of Senecionis Scandentis Herba. Therefore, it is necessary to strengthen the quality control of raw materials, establish a more comprehensive limited standard for PAs, and optimize the medication strategy in combination with traditional Chinese medicine theory to ensure the safety of clinical medication.
8.Toxic Mechanism, Risk Evaluation, and Regulatory Policies of Pyrrolizidine Alkaloids from Senecionis Scandentis Herba: A Review
Weili CHEN ; Shengxuan LI ; Linying QIN ; Xiangle MENG ; Yu DONG ; Long CHENG
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(21):330-338
ObjectiveTo summarize the research results on the toxic mechanism and the relevant regulatory policies at home and abroad of pyrrolizidine alkaloids (PAs), the main toxic components, in Senecionis Scandentis Herba, thereby providing insights into the clinical use and scientific regulation of Senecionis Scandentis Herba. MethodsMultiple Chinese and English databases including PubMed, ScienceDirect, Elsevier, China national knowledge infrastructure (CNKI), Wanfang Data, and VIP were searched, with "Senecio," "PSenecio scandens," and "pyrrolizidine alkaloids" as search terms. The relevant articles published from 1959 to 2025 were retrieved and analyzed, and 79 articles were finally selected for review. ResultsThe chemical components of Senecionis Scandentis Herba include alkaloids, flavonoids, volatile oils, sesquiterpenes, jacaranone derivatives, and organic acids, among which alkaloids are the most toxic components, followed by jacaranone derivatives. PAs are metabolized into highly active pyrrole derivatives in the liver, which can cause serious adverse reactions such as sinusoidal obstruction syndrome and DNA damage. The content of PAs varies significantly due to the origin, harvest period, and medicinal parts. There have been reports of clinical liver injury caused by preparations containing Senecionis Scandentis Herba, and some preparations have a daily intake of PAs exceeding the international safety threshold. Currently, international organizations have set limited standards for PAs, while China only controls the content of adonifoline, and the supervision is not yet perfect. ConclusionAlthough Senecionis Scandentis Herba has medicinal value, its PAs have significant toxicological properties. This is a problem that cannot be ignored and needs to be overcome in the use of Senecionis Scandentis Herba. Therefore, it is necessary to strengthen the quality control of raw materials, establish a more comprehensive limited standard for PAs, and optimize the medication strategy in combination with traditional Chinese medicine theory to ensure the safety of clinical medication.
9.Associations of sleep quality and weight stigma with depressive mood among college students
YANG Tian, ZHANG Xiuhong, ZHAO Li, DONG Yanhui, MA Jun, MAO Changming, YANG Qin
Chinese Journal of School Health 2026;47(9):1272-1276
Objective:
To investigate the associations of sleep quality and weight stigma with depressive mood among college students, so as to provide evidence for mental health promotion in higher education institutions.
Methods:
From September to November 2024, a stratified cluster random sampling method was used to survey 4 524 undergraduate students from the first to third year in comprehensive universities across various cities in Inner Mongolia. The χ 2 test was used to compare the detection rates of poor sleep quality, experiences of weight stigma, and depressive mood among students with different characteristics, and multivariate Logistic regression analysis was conducted to examine the independent and combined associations between sleep quality, the number of types of weight stigma experienced, and depressive mood.
Results:
Among students, the detection rate of poor sleep quality was 21.60%; those with experiences of weight stigma had a detection rate of 11.52%; those with depressive mood had a detection rate of 9.46%. Multivariate Logistic regression analysis showed that, compared with those who had good sleep quality, individuals with poor sleep quality were more likely to experience depressive mood [ OR (95% CI )=2.99(2.41- 3.71 )]; compared with those who had no experience of weight stigma, individuals who experienced ≥2 types of weight stigma were more likely to experience depressive mood [ OR (95% CI )=4.51(2.82-7.22)] (both P <0.01). Multivariate Logistic regression analysis, with "good sleep quality and no weight stigma experience" as the reference group, showed that all other joint groups had a higher likelihood of developing depressive mood, with the highest likelihood observed among students who had poor sleep quality and had experienced ≥2 types of weight stigma [ OR (95% CI )=14.21(6.95-29.06), P <0.01].
Conclusions
Poor sleep quality and a greater number of weight stigma types are both associated with depressive mood among college students. Mental health programs in higher education institutions should simultaneously address students sleep problems and weight related adverse experiences, and implement comprehensive interventions.
10.Mechanistic Interplay Between Remodeling of The Peritubular Capillary Microenvironment and Renal Fibrosis
Qi-Fa QIN ; Wen-Hui HUANG ; Jun-Yue HUANG ; Guang-Run ZHANG ; Rong XUE ; Rui QIAN ; Li-Li XU ; Li-Ting DONG
Progress in Biochemistry and Biophysics 2026;53(10):2647-2664
Renal fibrosis is the common pathological endpoint of many forms of chronic kidney disease (CKD), yet the mechanisms determining effective repair versus persistent fibrotic remodeling remain incompletely understood. Peritubular capillaries (PTCs) are not merely passive targets of fibrotic injury, but form a dynamic vascular microenvironment linking regional perfusion, oxygen delivery, tubular metabolism, endothelial barrier integrity, pericyte support, immune-cell trafficking, and extracellular matrix (ECM) remodeling. We propose that PTC abnormalities should not be interpreted simply as reduced capillary density, but as a multidimensional disturbance of microvascular structure and function. Structural vascular preservation does not necessarily indicate effective microcirculation: anatomically detectable capillaries may still exhibit impaired perfusion, barrier dysfunction, abnormal endothelial-pericyte interactions, disturbed oxygen metabolism, or reduced network connectivity. Conversely, increased angiogenesis does not necessarily signify successful vascular repair if vessels remain immature, poorly perfused, or inadequately integrated into the existing network. To organize these abnormalities, we conceptualize PTC remodeling into four predominant but nonexclusive states: endothelial barrier disruption with inflammatory adhesion; endothelial-pericyte uncoupling with no-reflow; dysregulated angiogenesis with network simplification; and capillary rarefaction with fibrotic matrix locking. These states are not sequential stages of CKD. They may coexist within the same kidney, overlap within the same anatomical region, and vary with disease etiology, injury phase, vascular compartment, and treatment exposure. We further propose six dimensions for evaluating PTC status—structural presence, functional perfusion, barrier integrity, pericyte coupling, oxygen metabolism, and network connectivity—so that vascular quantity, function, and reparative capacity are assessed separately rather than inferred from a single endothelial marker or capillary-density measurement. Mechanistically, these states converge on a bidirectional microvascular-fibrotic feedback loop. Barrier disruption facilitates leukocyte recruitment and alters vascular paracrine signaling. Endothelial-pericyte uncoupling compromises capillary stability, whereas abnormal pericyte contraction may increase local vascular resistance and contribute to no-reflow before overt capillary loss. Dysregulated angiogenesis may generate vessels that fail to mature or connect to an effective perfusion network. Progressive capillary rarefaction compromises oxygen delivery, while sustained tubular transport demand and mitochondrial dysfunction may aggravate regional oxygen supply-demand mismatch. Injured tubules, immune cells, endothelial cells, pericytes, and fibroblasts communicate through soluble mediators, extracellular vesicles, direct cell contact, and cell-matrix signaling. Importantly, fibrosis is not merely a downstream consequence of microvascular injury. Altered ECM may increase diffusion distance, modify mechanotransduction, impair endothelial survival and migration, and restrict capillary reopening and regeneration. We use the term matrix locking to describe this sustained constraint on vascular repair, while emphasizing that current evidence does not establish irreversible disease in humans. This framework also has therapeutic implications. PTC-directed treatment should not be reduced to increasing vessel number or uniformly promoting angiogenesis. Instead, intervention should be matched to the dominant and potentially reversible abnormality: preserving endothelial barrier function; restoring endothelial-pericyte stability and reducing pathological microvascular resistance; normalizing angiogenesis so that vascular growth is accompanied by maturation, barrier competence, network integration, and effective perfusion; and, in advanced rarefaction, relieving matrix-related constraints while supporting vascular regeneration. The context- and time-dependent effects of signaling through VEGF, Tie2, PDGF-B/PDGFRβ, eNOS/NO, and related pathways indicate that the same molecular signal may exert different effects depending on disease context and timing. Therapeutic efficacy should therefore be evaluated by restoration of effective microcirculation and tissue function rather than by isolated molecular changes or capillary counts alone. Despite increasing mechanistic evidence, the translational basis for this framework remains limited. Most causal and interventional data derive from animal or cell models, whereas human evidence is largely limited to pathological observations, patient-sample associations, and prognostic studies. Currently available circulating and urinary candidate biomarkers generally lack sufficient specificity for PTC injury or state assignment, and no standardized quantitative thresholds have been externally validated. The four-state model should therefore be regarded as a hypothesis-generating analytical framework rather than a clinicopathological classification system. Future studies should integrate spatially resolved tissue phenotyping, blood and urine biomarkers, and dynamic microcirculatory assessment in longitudinal cohorts. They should test reproducibility, assess prognostic value beyond conventional pathology, estimated glomerular filtration rate, and proteinuria, and determine whether changes in PTC status precede or mediate therapeutic benefit. Linking reproducible microvascular phenotypes to defined mechanisms, treatment response, and long-term renal outcomes will be essential to determine whether state-directed assessment and restoration of the PTC microenvironment can ultimately inform patient stratification and therapeutic decision-making.


Result Analysis
Print
Save
E-mail