Collagen is a major structural protein in the matrix of animal cells and the most widely distributed and abundant functional protein in mammals. Collagen’s good biocompatibility, biodegradability and biological activity make it a very valuable biomaterial. According to the source of collagen, it can be broadly categorized into two types: one is animal collagen; the other is recombinant collagen. Animal collagen is mainly extracted and purified from animal connective tissues by chemical methods, such as acid, alkali and enzyme methods, etc. Recombinant collagen refers to collagen produced by gene splicing technology, where the amino acid sequence is first designed and improved according to one’s own needs, and the gene sequence of improved recombinant collagen is highly consistent with that of human beings, and then the designed gene sequence is cloned into the appropriate vector, and then transferred to the appropriate expression vector. The designed gene sequence is cloned into a suitable vector, and then transferred to a suitable expression system for full expression, and finally the target protein is obtained by extraction and purification technology. Recombinant collagen has excellent histocompatibility and water solubility, can be directly absorbed by the human body and participate in the construction of collagen, remodeling of the extracellular matrix, cell growth, wound healing and site filling, etc., which has demonstrated significant effects, and has become the focus of the development of modern biomedical materials. This paper firstly elaborates the structure, type, and tissue distribution of human collagen, as well as the associated genetic diseases of different types of collagen, then introduces the specific process of producing animal source collagen and recombinant collagen, explains the advantages of recombinant collagen production method, and then introduces the various systems of expressing recombinant collagen, as well as their advantages and disadvantages, and finally briefly introduces the application of animal collagen, focusing on the use of animal collagen in the development of biopharmaceutical materials. In terms of application, it focuses on the use of animal disease models exploring the application effects of recombinant collagen in wound hemostasis, wound repair, corneal therapy, female pelvic floor dysfunction (FPFD), vaginal atrophy (VA) and vaginal dryness, thin endometritis (TE), chronic endometritis (CE), bone tissue regeneration in vivo, cardiovascular diseases, breast cancer (BC) and anti-aging. The mechanism of action of recombinant collagen in the treatment of FPFD and CE was introduced, and the clinical application and curative effect of recombinant collagen in skin burn, skin wound, dermatitis, acne and menopausal urogenital syndrome (GSM) were summarized. From the exploratory studies and clinical applications, it is evident that recombinant collagen has demonstrated surprising effects in the treatment of all types of diseases, such as reducing inflammation, promoting cell proliferation, migration and adhesion, increasing collagen deposition, and remodeling the extracellular matrix. At the end of the review, the challenges faced by recombinant collagen are summarized: to develop new recombinant collagen types and dosage forms, to explore the mechanism of action of recombinant collagen, and to provide an outlook for the future development and application of recombinant collagen.

BACKGROUND:Osteoporosis is a high-risk factor for dental implant treatment.The preparation of tissue engineering scaffolds with sustained-release Alendronate and its application in oral implant surgery for osteoporosis patients is a current hot topic in oral bone tissue engineering research.OBJECTIVE:To prepare alendronate/chitosan/polyvinyl alcohol composite hydrogel film and characterize its sustained release properties.METHODS:(1)Chitosan/polyvinyl alcohol composite hydrogel films with varying mass ratios(mass ratios of chitosan and polyvinyl alcohol were 3:7,5:5,and 7:3,respectively),chitosan and polyvinyl alcohol hydrogel films were prepared using a physical crosslinking method.By characterizing the morphology,water contact angle,mechanical properties,swelling rate,and cell compatibility of the hydrogel film,a suitable hydrogel film was screened as a carrier of alendronate.(2)Chitosan/polyvinyl alcohol composite hydrogel films containing 0,0.4,1.2,and 2.0 mg/L alendronate were prepared,and rat bone marrow mesenchymal stem cells were co-cultured with the four groups of hydrogel films.The cytocompatibility of the hydrogel films was detected by CCK-8 assay and CD44 immunofluorescence staining.The drug-loaded chitosan/polyvinyl alcohol composite hydrogel films were immersed in PBS.The drug release performance of the composite hydrogel films was detected by ultraviolet-visible spectroscopy.RESULTS AND CONCLUSION:(1)The characterization results showed that with the increase of the mass of polyvinyl alcohol in the hydrogel film,the structural density of the hydrogel film increased,the porosity decreased,the water contact angle(all within 90°),the elongation at break and the compressive strength increased,and the equilibrium swelling rate decreased.It had no effect on the proliferation of rat bone marrow mesenchymal stem cells.Chitosan hydrogel film could promote the adhesion of rat bone marrow mesenchymal stem cells.The 3:7 and 5:5 ratio composite hydrogel films did not affect the adhesion of rat bone marrow mesenchymal stem cells.Polyvinyl alcohol hydrogel film and 7:3 ratio composite hydrogel film inhibited the adhesion of rat bone marrow mesenchymal stem cells.Based on the above results,the 5:5 composite hydrogel film was selected as the carrier of alendronate.(2)CCK-8 assay results showed that the composite hydrogel film containing 0.4 and 1.2 mg/L alendronate had no cytotoxicity.CD44 immunofluorescence staining results showed that the composite hydrogel film containing 0.4 mg/L alendronate did not affect the adhesion of rat bone marrow mesenchymal stem cells,while the composite hydrogel film containing 1.2 and 2.0 mg/L alendronate inhibited the adhesion of rat bone marrow mesenchymal stem cells.Chitosan/polyvinyl alcohol composite hydrogel film containing 0.4,1.2,and 2.0 mg/L alendronate released alendronate in the first 6 hours,and then released alendronate evenly and stably,with a release time of more than 96 hours.(3)The results showed that the chitosan/polyvinyl alcohol composite hydrogel film with a ratio of 5:5 had good physical and chemical properties and cytocompatibility,and could be used as a sustained-release carrier of alendronate.

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

BACKGROUND:During the treatment of posterolateral tibial plateau fractures through the fibular head approach,the gap between the fibular head and the lateral plateau cannot accommodate the posterior placement of a plate for all patients.OBJECTIVE:To analyze,via finite element analysis,the differences in fixation strength resulting from varying the angles and quantities of horizontal arm variable angle screws in the plate during the treatment of posterolateral tibial plateau fractures through the fibular head approach.METHODS:A finite element model was established based on CT images of the knee to ankle joints of a 30-year-old healthy adult male volunteer.The models were divided into two categories:posteriorly placed group and non-posteriorly placed group based on whether the lateral locking compression plate was posteriorly placed.The posteriorly placed group was further subdivided into groups A-D based on the offset angle of the two variable angle screws(0°,5°,10°,and 15°).The non-posteriorly placed group was subdivided into groups E and F based on offset angles(0° and 15°).Finite element analysis was used to evaluate the von Mises stress distribution,maximum von Mises stress,and compressive displacement under loads of 250,500,and 750 N,exploring the mechanical differences between the groups.RESULTS AND CONCLUSION:(1)Finite element analysis results showed that under a 750 N load,the maximum compressive displacement trend of the internal fixation device was D＜B=C=F＜A＜E.The trend for maximum von Mises stress was B＜C＜A＜D＜F＜E.The trend for maximum compressive displacement on the bone was C=D＜B＜A＜F＜E,and for maximum von Mises stress,it was B＜C＜A＜F＜D＜E.The displacement and stress trends for the six models were similar under loads ranging from 250 N to 750 N.(2)These results suggest that for posterolateral tibial plateau fractures fixed through the fibular head approach,posterior placement of the plate should aim to accommodate two screws.If only one screw can be fixed during surgery,variable angle screws should be offset in the range of 0-15° to increase the probability of securing two screws.

Aim To evaluate the role of the glucose transporter protein 1(GLUT1)-dependent glycolytic in the attenuation of oxygen-glucose deprivation-reoxygen-ation(OGD/R)injury in HK-2 cells by dexmedetomi-dine(Dex).Methods C57/BL6 mice were random-ly divided into three groups(n=6),namely,sham operation group(Sham group),renal ischemia reper-fusion group(I/R group)and Dex group(I/R+Dex group).Serum creatinine(Cr)and urea nitrogen(BUN)were measured,while the levels of key glyco-lytic enzymes HK2,PFKFB3 and GLUT1 were meas-ured.HK-2 cells were cultured and randomised into seven groups(n=6),which was treated with OGD/R,overexpression or interference with GLUT1,Dex and glycolysis inhibitor 2-DG.CCK-8 and LDH activi-ty were used to detect cellular damage.Glycolysis lev-els were detected by lactate and ECAR.The inflamma-tory level was reflected by qRT-PCR for IL-6 and TNF-α.qRT-PCR and Western blot were performed to de-tect the levels of GLUT1,HK2,and PFKFB3.Results Dex significantly ameliorated kidney injury and HK-2 cell injury(P＜0.05).Dex inhibited the OGD/R-induced rise in lactate and extracellular acidification rate(ECAR),as evidenced by suppression of the ex-pression of GLUT1,HK2 and PFKFB3(P＜0.05).In vitro experiments showed that GLUT1 knockdown sig-nificantly improved OGD/R-induced cellular damage.Lactate,ECAR,glycolysis-related mRNAs and pro-teins were inhibited by GLUT1 knockdown(P＜0.05).Significantly,there were no significant differ-ences in above indexes after Dex treatment based on GLUT1 knockdown.Overexpression of GLUT1 abroga-ted the protective effects of Dex,while reversing the inhibitory effects of Dex on the expression of GLUT1,HK2,and PFKFB3(P＜0.05).Conclusions Dexmedetomidine attenuates OGD/R induced injury in HK-2 cells by inhibiting GLUT1-dependent glycolysis.

Objective:To evaluate the clinical efficacy of Tianma Xionglin Zhixuan Tablets in treating hypertension patients with liver yang hyperactivity or comorbid phlegm-stasis syndrome and explore its therapeutic mechanisms through plasma metabolomics.Methods:Thirty-six hypertension patients(4 dropouts)diagnosed with liver yang hyperactivity or phlegm-stasis syndrome were enrolled as the treatment group from June 2022 to September 2023 at the First Affiliated Hospital of Hunan University of Chinese Medicine,while 30 healthy volunteers with balanced constitutions were recruited as the blank group.Plasma samples were collected from patients pre-and post-treatment and from healthy volunteers.Clinical outcomes,including syndrome scores,office blood pressure(BP),and 24-hour ambulatory BP,were recorded.Plasma metabolomic profiling was performed using liquid chromatography-mass spectrometry(LC-MS).Results:Compared with baseline,Tianma Xionglin Zhixuan Tablets significantly reduced traditional Chinese medicine syndrome scores(P＜0.01),office systolic/diastolic BP(P＜0.01),and 24-hour ambulatory BP parameters(24-hour mean BP,daytime/nighttime mean BP;all P＜0.01).Metabolomic analysis identified 45 differential metabolites between the blank group and pretreatment patients,and 64 metabolites altered post-treatment(VIP＞1,P＜0.05).Enrichment analysis of 16 overlapping endogenous metabolites revealed that Tianma Xionglin Zhixuan Tablets primarily modulated arachidonic acid metabolism and sphingolipid metabolism pathways.Conclusion:Tianma Xionglin Zhixuan Tablets demonstrates significant clinical efficacy in hypertension patients with liver yang hyperactivity or phlegm-stasis syndrome,potentially mediated through regulation of arachidonic acid and sphingolipid metabolism.

AIM To investigate the protective effects of verbascoside on D-galactose-induced liver injury in mice and its underlying mechanisms.METHODS C57BL/6J mice were randomly assigned to the normal group,the model group,the vitamin E group(100 mg/kg),and the low-dose and high-dose verbascoside groups(40,80 mg/kg),with 10 mice in each group.Simultaneous administration of medicine and subcutaneous injection of D-galactose(600 mg/kg)went on among the groups except the normal group for 8 weeks.Serum ALT,AST,ALP activities,along with TBil levels were measured using biochemical kits.Hepatic GSH,MDA concentrations,as well as SOD and GSH-Px activities were quantified.Liver pathological morphology was evaluated by HE staining,while hepatic fibrosis area was assessed using Sirius red staining.Western blot analysis determined hepatic expression of IL-6,IL-1β,TNF-ɑ,TLR4,NF-κB p65,IκBɑ and p-IKBɑ proteins.RESULTS Compared to the model group,the groups treated with vitamin E or verbascoside demonstrated significantly reduced body weight(P＜0.05,P＜0.01);increased hepatic index(P＜0.05,P＜0.01);decreased serum activities of ALT,AST and ALP alongsided reduced TBil levels(P＜0.05,P＜0.01);attenuated pathological damage of liver tissue and fibrosis severity;reduced hepatic MDA level(P＜0.05,P＜0.01);and elevated GSH level with enhanced SOD and GSH-Px activities(P＜0.05,P＜0.01).Furthermore,the high-dose verbascoside group showed significantly decreased hepatic expressions of IL-6,IL-1 β,TNF-ɑ,TLR4,NF-κB p65,and p-IKBɑ/IKBɑ proteins(P＜0.05,P＜0.01).CONCLUSION Verbascoside improves D-galactose-induced liver injury through its antioxidant activity,anti-inflammatory effects,and suppression of the TLR4/NF-κB signaling pathway.

AIM To investigate the tumor-suppressive mechanism of Guiqi Yiyuan Extract combined with cisplatin in Lewis lung cancer mice.METHODS Ten intact C57BL/6J mice were assigned to the blank group.Sixty additional mice were developed into Lewis lung cancer models bearing transplanted tumor and subsequently allocated into the model group,the cisplatin group(5 mg/kg),the high-dose Guiqi Yiyuan Extract group(6.6 g/kg),and the low-dose,medium-dose and high-dose Guiqi Yiyuan Extract combined with cisplatin group(1.6,3.3,6.6 g/kg+5 mg/kg),with 10 mice in each group.Mice in the blank and model groups received saline via daily gavage,while treatment groups were administered Guiqi Yiyuan Extract orally(once daily),and cisplatin injection intraperitoneally(once every other day).After 14 days of drug administration,mice were euthanized for endpoint analysis.The following assessments were conducted:general health status and body weight changes monitored throughout the study period;tumor excision and weighing for inhibition rate calculation;histopathological examination of tumors via hematoxylin-eosin(HE)staining;serum quantification of IL-1 β,IL-18 and HMGB1 by ELISA;ultrastructural analysis of tumor cell death using transmission electron microscopy(TEM);spatial localization of TXNIP and GSDMD-N in tumor sections via immunofluorescence(IF);and Western blot detection of TXNIP,NLRP3,Caspase-1,cleaved Caspase-1,GSDMD,GSDMD-N protein expressions in tumor tissues.RESULTS Compared to the model group,the cisplatin group and all combination therapy groups exhibited significant reduction in tumor weight(P＜0.05)and increased tumor suppression rate;enhanced tumor tissue necrosis with characteristic pyroptotic morphology;elevated serum levels of IL-1β,IL-18 and HMGB1(P＜0.05);and upregulated expressions of pyroptosis-associated proteins TXNIP,NLRP3,Caspase-1,cleaved Caspase-1,GSDMD and GSDMD-N(P＜0.05).The high dose combination group demonstrated optimal therapeutic efficacy(P＜0.05).CONCLUSION Guiqi Yiyuan Extract enhances cisplatin sensitivity,demonstrating synergistic anti-tumor effects in Lewis lung carcinoma-bearing mice.This combinatorial therapeutic effect likely involves modulation of the TXNIP/NLRP3/Caspase-1/GSDMD pathway.

Aim To investigate the protective effect of Vaccarin(Va)on epithelial-mesenchymal transition(EMT)in renal fibrosis model mice through regulating STAT3,and the underlying mechanism.Methods Left ureter ligation was used to establish a mouse model of unilateral ureteral obstruction(UUO);human kid-ney tubular epithelial(HK2)cells were induced to differentiate by transforming growth factor-β(TGF-β)in vitro.HE and Masson staining were used to observe the morphological changes of renal tissue;kits were used to detect the levels of BUN,Cr,IL-1β and IL-7 in mouse serum;CCK-8 was used to detect the effect of Va on the viability of HK2 cells;RT-PCR was used to detect the levels of inflammatory factors in HK2 cells;Western blot was used to detect the expression of STAT3,p-STAT3,E-cadherin,and α-SMA proteins in renal tissue and HK2 cells;to further investigate the regulation of Va on STAT3,JAK/STAT3 pathway acti-vator RO8191 was used to treat TGF-β-induced HK2 cells,and functional loss was detected.Results Va improved the pathological damage in UUO mice,inhibi-ted the levels of BUN,Cr and inflammatory factors;Va inhibited the phosphorylation of STAT3,upregulated E-cadherin,and downregulated α-SMA protein expres-sion;RO8191 counteracted the inhibitory effect of Va on the phosphorylation of STAT3.Conclusions Va inhibits the phosphorylation of STAT3 and the release of inflammatory factors,improves EMT,thus exerting an anti-renal fibrosis effect.

Objective To evaluate the efficacy and safety of a novel intravascular lithotripsy(IVL)balloon—Vesscrack shockwave balloon—for vascular preparation before stent implantation in patients with severe coronary artery calcification(CAC).Methods This was a prospective,single-arm,multicenter study conducted in China from June 2022 to October 2022.Patients with severe CAC were treated with the Vesscrack shockwave balloon for lesion preparation,followed by drug-eluting stent(DES)implantation.Of these,33 patients underwent optical coherence tomography(OCT).The primary endpoint was procedural success,defined as successful stent implantation with residual stenosis≤30％and the absence of in-hospital major adverse events,including cardiac death,target vessel-related myocardial infarction,or target lesion revascularization.Results A total of 170 patients[mean age:(65.9±7.9)years,116 males]were enrolled.After treatment with IVL and DES,the minimum lumen diameter increased significantly compared to baseline[(2.34±0.40)mm vs.(0.95±0.33)mm,P＜0.001],the degree of stenosis was significantly reduced[(13.24±6.60)％vs.(65.18±10.59)％,P＜0.001].Procedural success was achieved in 100％of cases,and device success was 98.8％.The 30-day patient-related cardiovascular clinical composite endpoint(POCE)rate was 0.0,with no target lesion failure,no confirmed or potential thrombotic events were observed.The shockwave energy generator demonstrated excellent stability and ease of use.Among the 33 patients assessed with OCT,after IVL intervention,the maximum calcified area of the lumen[(3.51±1.51)mm2 vs.(2.85±1.80)mm2,P＜0.001],and the minimum lumen area within the target lesion[(3.08±1.04)mm2 vs.(2.02±0.75)mm2,P＜0.001],and after DES intervention,the luminal area of the largest calcified site[(6.59±1.64)mm2 vs.(2.85±1.80)mm2,P＜0.001]and the minimum luminal area within the target lesion[(6.19±1.45)mm2 vs.(2.02±0.75)mm2,P＜0.001]were significantly increased,and the differences were statistically significant.Conclusions The Vesscrack shockwave balloon is effective and safe for vascular preparation in patients with severe CAC prior to stent implantation.It achieves significant calcified plaque modification,high procedural success rates,and minimal complications.