Culture in vitro and Cryopreservation of Shouguang Black Chicken Fibroblasts

[Objective] The aim of this study was to establish the in vitro culture system of chicken fibroblasts.[Method] Tissue explant method and enzymatic digestion method were used to separate and culture chicken skin fibroblasts respectively.The rate of cell growth,cryopreservation and recovery were compared.[Result] The primary chicken fibroblasts prepared by enzymatic digestion grew faster and converged together to form monolayer on 5 d post preparation;the passage cells prepared by these 2 methods grew at similar speed and formed monolayer within 2-3 d;homogeneous fibroblasts could be obtained by trypsin digestion and repeated attachment for 3-4 passages;there were 75%-80% of cells survived after cryopreservation and recovery;the growth curves of embryonic fibroblasts and skin fibroblasts were all normal and the two kind of cells still retained the normal number of chromosomes even at the twelfth passage.[Conclusion] The feeder layer cells needed for establishing ES cell lines could be obtained by culturing chicken fibroblasts through both tissue explant method and enzymatic digestion method.This study provided a basis for the successful establishment of ES cell lines.

Preservation of Juniperus thurifera L.:a rare endangered species in Algeria through in vitro regeneration

Juniperus thurifera L.is an endemic Cupres saceae from the Aure`s Mountains of north eastern Algeria and endangered,in part,due to the scarcity of viable seeds It is threatened by other abiotic factors and the lack of an effective management strategy will increase its risk o extinction.The dearth of information on its in vitro regeneration impedes its application in forest managemen programs.We therefore developed a micropropagation protocol using microcuttings with auxiliary buds.Cuttings were grown on different combinations of media supplemented with plant growth regulators at different concentrations.The highest number of shoots and branches regenerated from original shoots was obtained on Woody Plant Medium(WPM)supplemented with 6-benzylaminopurine(BAP)(0.5 mg L^(-1))and 2,4-dichlorophe noxyacetic acid(2,4-D)(0.25 mg L^(-1)).The best elongation of shoots was achieved with WPM supplemented with0.5 mg L^(-1)of BAP and 0.25 or 1 mg L^(-1) of 2,4-D.On the second subculture,shoots had a higher number of branches than those of the first.The highest rooting rate,38.8%,was obtained with shoots cultured in 1/2 Murashige and Skoog(MS)medium supplemented with 5.0 mg L^(-1)each of indol-3-butyric(IBA)and naphthalene acetic acid(NAA).Similarly,the highest root numbers and lengths were produced on 1/2 MS medium supplemented with IBA and NAA(5.0 mg L^(-1)each).During transfer to acclimatization,rates of plant losses of 50% occurred.The second part of the experiment showed that the best shoot callusing was on WPM supplemented with BAP and 2,4-D,with either the combination 0.5+0.25 or 0.25+0.25 mg L^(-1).The results of this research provide a starting point for further studies on in vitro regeneration of J.thurifera for the sustainable management of its unique ecosystem in the Mediterranean basin.

Effects of Ovarian Preservation Time on in vitro Maturation and in vitro Fertilization of Oocytes from Slaughtered Sheep

[Objectives] The aim was to study the effects of ovarian preservation time on in vitro fertilization of oocytes from slaughtered sheep. [Methods] The collected ovaries were randomly and evenly divided into four groups. They were preserved in physiological saline containing penicillin（ 100 IU/ml） and streptomycin（ 100 μg/ml） at 15-20 ℃ for 0（ Control）,6,12 and 18 h,respectively. Then,the oocytes were subjected to in vitro fertilization. [Results]The maturation rates,cleavage rates and blastocyst rates of the oocytes preserved for 6 and 12 h showed no significant differences compared with those of the oocytes preserved for0 h（ 72. 03%,70. 87% vs. 73. 68%; 74. 12%,72. 60% vs. 74. 49%; 22. 22%,20. 75% vs. 23. 29%）（ P 〉 0. 05）. There were also no significant differences in maturation rate,cleavage rate or blastocyst rate between the oocytes preserved for 18 and 0 h（ P 〉 0. 05）. [Conclusions] Within a certain rage（ 0-18 h）,storage time of ovary at 15-20 ℃ does not affect the continued development of oocytes from slaughtered sheep.

Influence of Preservation Solutions and Bile on a Human Bile Duct Epithelium Cell Line: An <i>In-Vitro</i>Study

Introduction: Bile duct complications are common after liver transplantation. The impact of preservation solution is unclear. Aim: We investigated the impact of different preservation solutions with and without diluted bile on a human biliary tract carcinoma cell line. Methods: The human biliary tree carcinoma cell line SK-ChA-1 was cultured with either medium or University of Wisconsin solution (UW), histidine-tryptophane-ketoglutarate (HTK) solution, Celsior or physiological saline for 6h, 10h or 12h at 6℃- 8℃ and metabolic activity was measured by a MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium)-test immediately, after 12h or 24h. Cells were also incubated in combination with diluted porcine bile. Results: Immediately after cold storage of 6h HTK and UW decreased metabolic activity whereas Celsior increased metabolic activity after 10h or 12h of cold ischemia. After 12h or 24h no major differences were found any more. Incubation with bile in combination with HTK, Celsior or NaCl decreased metabolic activity, whereas UW abolished this effect. Conclusion: On a cellular level differences between preservation solutions were found, especially in combination with bile. Further studies are warranted to determine whether this results in clinically significant differences in biliary complications.

Preservation of Disease-free Shoot Tips of Potato Germplasm through in vitro System

The present investigation was undertaken to find out the best medium composition for medium-term preservation of disease free potato shoot tips in in vitro system.Thirteen potato genotypes and fourteen treatments were taken under consideration for the present experiment.Among fourteen treatments,mannitol and sorbitol containing media proved to be the best for medium-term preservation of potato shoot tips.High concentration of mannitol delayed root formation.

Preparation, cryopreservation and in vitro culture of spermatogonial stem cells of new born calves

The experiment was designed to study the preparation, cryopreservation and culture of calf spermatogonial stem cells in order to provide some data for theoretical research and practical use of calf spermatogonial stem cells. As for enzymolysis of testis tissue, two digestive method A and B. The cryopreservation cooling procedure was that spermatogonial stem cells was equilibrated at 4℃ for lh, at -20℃ for lh, at -40℃ for 2h, at -80℃ overnight and then stored in liquid nitrogen. The different concentration of three eryoprotectants were compared. The results indicated that both method A and method B achieved the same high motility rates of cells with method B needing time longer, calf spermatogonial stem cells could be well cryopreserved by the stage cooling procedure. Satisfactory cryopreservative results were gotten by adding 10% DMSO or 10% EG to cryopreservative medium, the former was better and adding sucrose could improved cryopreservative effect. The culture behaviors of spermatogonial stem cells kept the same before and after cryopreservation. It was concluded that an effective method was verified for preparation, cryopreservation and culture of new calf spermatogonial stem cells.

in vitro新型评价体系研究海洋生物活性物质作为口腔护理材料的应用特性

对氨甲环酸、托玛琳、胶原蛋白、壳寡糖和FGFC1的止血、抗炎和抑菌能力进行了评价。构建了一种新的in vitro止血系统评价体系,结合血小板内cAMP和TXA2的变化来评价5种材料的止血能力。同时通过测定5种材料对细胞内IL-6、IL-1β和TNF-α含量,以及对典型口腔致病菌的抑制作用评定其抗炎和抑菌效果。氨甲环酸、壳寡糖、胶原蛋白肽、托玛琳的血小板聚集促进率超过15%,壳寡糖和FGFC1具有显著抗炎能力(P<0.05),壳寡糖还具有抑菌效果。因此,胶原蛋白和壳寡糖具有抑制牙龈上皮细胞炎症和一定的牙龈止血作用,壳寡糖在抑制口腔致病菌的新型口腔护理产品的应用上具有良好前景。

Oxygen tension modulates cell function in an in vitro three-dimensional glioblastoma tumor model

Hypoxia is a typical feature of the tumor microenvironment,one of the most critical factors affecting cell behavior and tumor progression.However,the lack of tumor models able to precisely emulate natural brain tumor tissue has impeded the study of the effects of hypoxia on the progression and growth of tumor cells.This study reports a three-dimensional(3D)brain tumor model obtained by encapsulating U87MG(U87)cells in a hydrogel containing type I collagen.It also documents the effect of various oxygen concentrations(1%,7%,and 21%)in the culture environment on U87 cell morphology,proliferation,viability,cell cycle,apoptosis rate,and migration.Finally,it compares two-dimensional(2D)and 3D cultures.For comparison purposes,cells cultured in flat culture dishes were used as the control(2D model).Cells cultured in the 3D model proliferated more slowly but had a higher apoptosis rate and proportion of cells in the resting phase(G0 phase)/gap I phase(G1 phase)than those cultured in the 2D model.Besides,the two models yielded significantly different cell morphologies.Finally,hypoxia(e.g.,1%O2)affected cell morphology,slowed cell growth,reduced cell viability,and increased the apoptosis rate in the 3D model.These results indicate that the constructed 3D model is effective for investigating the effects of biological and chemical factors on cell morphology and function,and can be more representative of the tumor microenvironment than 2D culture systems.The developed 3D glioblastoma tumor model is equally applicable to other studies in pharmacology and pathology.

Adsorption,in vitro digestion and human gut microbiota regulation characteristics of three Poria cocos polysaccharides

Poria cocos(PC)is a famous traditional Chinese medicine(TCM)and a widely used healthcare ingredient,which has antiobesity,enhancing immunity and improving sleep effects.Traditionally,only water-soluble poria polysaccharide(WSP)is extracted and applied for clinical application,while insoluble polysaccharide(alkali-soluble poria polysaccharide,ASP)is discarded as herb residue.However,the whole PC has also been historically utilized as functional herbal food.Considering the beneficial role of dietary fiber and the traditional use of PC,ASP may also contribute substantially to the therapy function of PC.Compared to WSP,little attention has been paid to ASP and ASP modified product carboxymethyl poria polysaccharide(CMP)which has been used as an antitumor adjuvant drug.In this study,the oil,cholesterol,metal ions and polyphenols adsorption ability,in vitro simulated digestive and the gut microbiota fermentation characteristics of WSP,ASP and CMP were studied to evaluate the functional values of three P.cocos polysaccharides(PCPs).The results showed that all three PCPs had good adsorption capacity on cholesterol,polyphenols and metal ions(Cd^(2+)/Zn^(2+)/Mg^(2+)),among which ASP showed the highest capacity than WSP and CMP.The adsorption capacity of all three PCPs on heavy metal ions(Cd^(2+)/Zn^(2+))was stronger than that of non-heavy metal ions(Mg^(2+));The in vitro digestibility of all three PCPs was very low,but WSP was slightly higher than ASP and CMP;Moreover,the indigestible residue of all three PCPs could improve the richness and diversity of gut microbiota,among which ASP had the greatest influence.In general,ASP and CMP could significantly promote the proliferation of some probiotics and inhibit the growth of some harmful bacteria.The gut microbiota diversity of CMP was reduced,but the richness of probiotics,especially Parabacteroides distasonis was significantly enhanced compared with the ASP group,and the growth of harmful bacteria Klebsiella pneumoniae was inhibited after CMP treatment.The short-chain fatty acids(SCFAs)analysis results showed that all three PCPs could significantly promote the production of acetic acid,propionic acid and the total acid content compared with blank control group,and SCFAs producing activity was positively correlated with the proliferative capacity of probiotics.Taken together,the good adsorption characteristics and gut microbiota regulatory activity of ASP may lay foundation for its lipid-lowering and immune-improving function.Additionally,the probiotic effect of CMP and ASP indicated that except for only use the water extract of PC in clinic,CMP and ASP also can be used in healthcare to take full advantage of this valuable medicine.

Corrosion and in vitro cytocompatibility investigation on the designed Mg-Zn-Ag metallic glasses for biomedical application

In the present work,seven Mg-Zn-Ag alloys with the nominal composition of Mg_(96-x)Zn_(x)Ag_(4)(x=17,20,23,26,29,32,35 in at.%)were prepared by induction melting and single-roller melt-spinning.The X-ray diffraction(XRD)analyses indicate the metallic glasses with three composition of Mg_(73)Zn_(23)Ag_(4),Mg_(70)Zn_(26)Ag_(4),and Mg_(67)Zn_(29)Ag_(4)were obtained successfully.The differential scanning calorimetry(DSC)measurement was used to obtain the characteristic temperature of Mg-Zn-Ag metallic glasses for the glass-forming ability analysis.The maximum glass transition temperature(Trg)was found to be 0.525 with a composition close to Mg_(67)Zn_(29)Ag_(4),which results in the best glass-forming ability.Moreover,the immersion test in simulated body fluid(SBF)demonstrate the relative homogeneous corrosion behavior of the Mg-Zn-Ag metallic glasses.The corrosion rate of Mg-Zn-Ag metallic glasses in SBF solution decreases with the increase of Zn content.The sample Mg_(67)Zn_(29)Ag_(4)has the lowest corrosion rate of 0.19mm/yr,which could meet the clinical application requirement well.The in vitro cell experiments show that the Madin-Darby canine kidney(MDCK)cells cultured in sample Mg_(67)Zn_(29)Ag_(4)and its extraction medium have higher activity.However,the Mg-Zn-Ag metallic glasses exhibit obvious inhibitory effect on human rhabdomyosarcoma(RD)tumor cells.The present investigations on the glass-forming ability,corrosion behavior,cytocompatibility and tumor inhibition function of the Mg-Zn-Ag based metallic glass could reveal their biomedical application possibility.

Effect of wall-disruption on nutrient composition and in vitro digestion of camellia and lotus bee pollens

The nutrient digestion,absorption and biological activity of bee pollen may be limited due to the complex pollen wall.Here,the effect of superfine grinding technology on the release of nutrients from bee pollen were investigated,and their antioxidant activities and in vitro digestion were explored in this study.Results showed that the content of nutrients in bee pollen increased after wall disruption.Among them,fat content increased by 22.55%-8.31%,protein content increased by 0.54%-4.91%,starch content increased by 36.31%-48.64%,soluble sugar content increased by 20.57%-29.67%,total phenolic acid content increased by 11.73%-86.98%and total flavonoids content increased by 14.29%-24.79%.At the same time,the antioxidant activity increased by 14.84%-46.00%.Furthermore,the active components such as phenolic compounds in the wall-disruption bee pollen were more readily to be released during the in vitro digestion,and easier to be absorbed because of their higher bioaccessibility.Antioxidant activities during in vitro digestion were also improved in walldisruption bee pollen.These findings provide evidence that bee pollen wall disruption was suggested,thus,it is more conducive to exerting the value of bee pollen in functional foods.

Network pharmacology study and in vitro experimental validation of Xiaojianzhong decoction against gastric cancer

BACKGROUND Cancer is one of the most serious threats to human health worldwide.Conventional treatments such as surgery and chemotherapy are associated with some drawbacks.In recent years,traditional Chinese medicine treatment has been increasingly advocated by patients and attracted attention from clinicians,and has become an indispensable part of the comprehensive treatment for gastric cancer.AIM To investigate the mechanism of Xiaojianzhong decoction(XJZ)in the treatment of gastric cancer(GC)by utilizing network pharmacology and experimental validation,so as to provide a theoretical basis for later experimental research.METHODS We analyzed the mechanism and targets of XJZ in the treatment of GC through network pharmacology and bioinformatics.Subsequently,we verified the impact of XJZ treatment on the proliferative ability of GC cells through CCK-8,apoptosis,cell cycle,and clone formation assays.Additionally,we performed Western blot analysis and real-time quantitative PCR to assess the protein and mRNA expression of the core proteins.RESULTS XJZ mainly regulates IL6,PTGS2,CCL2,MMP9,MMP2,HMOX1,and other target genes and pathways in cancer to treat GC.The inhibition of cell viability,the increase of apoptosis,the blockage of the cell cycle at the G0/G1 phase,and the inhibition of the ability of cell clone formation were observed in AGS and HGC-27 cells after XJZ treatment.In addition,XJZ induced a decrease in the mRNA expression of IL6,PTGS2,MMP9,MMP2,and CCL2,and an increase in the mRNA expression of HOMX1.XJZ significantly inhibited the expression of IL6,PTGS2,MMP9,MMP2,and CCL2 proteins and promoted the expression of the heme oxygenase-1 protein.CONCLUSION XJZ exerts therapeutic effects against GC through multiple components,multiple targets,and multiple pathways.Our findings provide a new idea and scientific basis for further research on the molecular mechanisms underlying the therapeutic effects of XJZ in the treatment of GC.

Assessing fertility preservation strategies: A scoping review

Objective:To describe the various options available for preserving female and/or male fertility,taking into account both social and medical aspects,and to identify the effects of different natural products on male infertility extracted from plants.Methods:We reviewed the literature and included full-text publications in English provided by international biomedical databases,including Sciences Direct,Google Scholar,OVID,PubMed,and MEDLINE between 2016 and 2023.Search terms,such as fertility preservation,in vitro maturation,cryopreservation,plants for the treatment of male infertility,were taken from Medical Subject Headings(MeSH)and Boolean operators were used to improve sensitivity.Results:112 papers were identified in the initial search,of which 18 were excluded due to duplication.After reviewing titles and abstracts,70 papers were finally included.The main findings of this study are presented under three key themes:gametogenesis,fertility preservation techniques,and plant-based alternatives.Regarding gametogenesis,significant progress has been made in understanding oocyte and sperm maturation,with optimized conditions improving maturation rates and motility.For fertility preservation,techniques such as rescue in vitro maturation and cryopreservation have shown the enhanced outcomes,particularly in maintaining gamete quality.Lastly,plant-based alternatives,including extracts and essential oils,have demonstrated potential in reducing oxidative stress,improving sperm motility,and supporting oocyte development,thus providing a promising complementary approach to conventional methods.Conclusions:Fertility preservation is achieved in a variety of ways,including oocyte and embryo vitrification and sperm cryopreservation,and the use of plant-based treatment of male infertility.

Simulation and fabrication of in vitro microfluidic microelectrode array chip for patterned culture and electrophysiological detection of neurons

To enable the detection and modulation of modularized neural networks in vitro,this study proposes a microfluidic microelectrode array chip for the cultivation,compartmentalization,and control of neural cells.The chip was designed based on the specific structure of neurons and the requirements for detection and modulation.Finite-element analysis of the chip’s flow field was conducted using the COMSOL Multiphysics software,and the simulation results show that the liquid within the chip can flow smoothly,ensuring stable flow fields that facilitate the uniform growth of neurons within the microfluidic channels.By employing MEMS technology in combination with nanomaterial modification techniques,the microfluidic microelectrode array chip was fabricated successfully.Primary hippocampal neurons were cultured on the chip,forming a well-defined neural network.Spontaneous electrical activity of the detected neurons was recorded,exhibiting a 23.7%increase in amplitude compared to neuronal discharges detected on an open-field microelectrode array.This study provides a platform for the precise detection and modulation of patterned neuronal growth in vitro,potentially serving as a novel tool in neuroscience research.

Investigation of bioactivity and biodegradability of Mg-bioceramic implants:An in vitro study for biomedical applications

In this study,Mg-based composites,by the addition of ZnO,Ca_(2)ZnSi_(2)O_(7),Ca_(2)MgSi_(2)O_(7),and CaSiO_(3)as bioactive agents,were fabricated using friction stir processing.The microstructure and in vitro assessment of bioactivity,biodegradation rate,and corrosion behavior of the resultant composites were investigated in simulated body fluid(SBF).The results showed that during the immersion of composites in SBF for 28 d,due to the release of Ca^(2+)and PO_(4)^(3-)ions,hydroxyapatite(HA)crystals with cauliflower shaped morphology were deposited on the surface of composites,confirming good bioactivity of composites.In addition,due to the uniform distribution of bioceramic powders throughout Mg matrix,grain refinement of the Mg matrix,and uniform redistribution of secondary phase particles,the polarization resistance increased,and the biodegradation rate of composites significantly reduced compared to monolithic Mg matrix.The polarization corrosion resistance of Mg-ZnO increased from 0.216 to 2.499 kΩ/cm^(2)compared to monolithic Mg alloy.Additionally,Mg-ZnO composite with the weight loss of 0.0217 g after 28 d immersion showed lower weight loss compared to other samples with increasing immersion time.Moreover,Mg-ZnO composite with the biodegradation rate of 37.71 mm/a exhibited lower biodegradation rate compared to other samples with increasing immersion time.

Microfluidic thermotaxic selection of highlymotile sperm and in vitro fertilization

The selection of the most motile and functionally competent sperm is an essential basis for in vitro fertilization(IVF)and normal embryonic development.Widely adopted clinical approaches for sperm sample processing intensely rely on centrifugation and wash steps that may induce mechanical damage and oxidative stress to sperm.Although a few microfluidic sperm sorting devices may avoid these adverse effects by exploiting intrinsic guidance mechanisms of sperm swimming,none of these approaches have been fully validated by clinical-grade assessment criteria.In this study,a microfluidic sperm sorting device that enables the selection of highly motile and functional sperm via their intrinsic thermotaxis is presented.Bioinspired by the temperature microenvironment in the fallopian tube during natural sperm selection,a microfluidic device with controllable temperature gradients along the sperm separation channel was designed and fabricated.This study investigated the optimal temperature conditions for human sperm selection and fully characterized thermotaxis-selected sperm with 45 human sperm samples.Results indicated that a temperature range of 35–36.5℃along the separation channel significantly improves human sperm motility rate((85.25±6.28)%vs.(60.72±1.37)%;P=0.0484),increases normal sperm morphology rate((16.42±1.43)%vs.(12.55±0.88)%;P<0.0001),and reduces DNA fragmentation((7.44±0.79)%vs.(10.36±0.72)%;P=0.0485)compared to the nonthermotaxis group.Sperm thermotaxis is species-specific,and selected mouse sperm displayed the highest motility in response to a temperature range of 36–37.5℃ along the separation channel.Furthermore,IVF experiments indicated that the selected sperm permitted an increased fertilization rate and improved embryonic development from zygote to blastocyst.This microfluidic thermotaxic selection approach will be translated into clinical practice to improve the IVF success rate for patients with oligozoospermia and asthenozoospermia.

The in vitro digestion fates of diacylglycerol under different intestinal conditions:a potential lipid source for lipid indigestion patients

The in vitro digestion models mimicking the gastrointestinal(GI)tract of general population and lipid indigestion patients(with lower levels of bile salts or pancreatic lipase)were selected to investigate whether diacylglycerols(DAGs)are potential good lipid sources for these patients.Linseed oil-based DAG(LD)and linseed oil(LT)were selected.LD-based emulsion((83.74±1.23)%)had higher lipolysis degree than LT-based emulsion((74.47±1.16)%)when monitoring the GI tract of normal population as previously reported.Indigestion conditions seriously decreased the digestive degree of LT-based emulsion((40.23±2.48)%-(66.50±3.70)%)while showed less influence on LD-based emulsion((64.18±2.41)%-(81.85±3.45)%).As opposed to LT-based emulsion,LD-based emulsion exhibited preference for releasing unsaturated fatty acids(especially oleic acid andα-linolenic acid)due to their different glycerolipid compositions.LD-based emulsion showed potential for providing lipids and nutrients(including essential fatty acids)for lipid indigestion patients.

Association between Exposure of Rare Earth Elements and Outcomes of In Vitro Fertilization-Embryo Transfer in Beijing

Objective The study aimed to investigate the impact of rare earth elements(REEs)exposure on pregnancy outcomes of in vitro fertilization-embryo transfer(IVF-ET)by analyzing samples from spouses.Methods A total of 141 couples were included.Blood and follicular fluid from the wives and semen plasma from the husbands,were analyzed for REEs using inductively coupled plasma mass spectrometry(ICP-MS).Spearman's correlation coefficients and the Mann–Whitney U test were used to assess correlations and compare REE concentrations among three types of samples,respectively.Logistic models were utilized to estimate the individual REE effect on IVF-ET outcomes,while BKMR and WQS models explored the mixture of REE interaction effects on IVF-ET outcomes.Results Higher La concentration in semen(median 0.089 ng/mL,P=0.03)was associated with a lower fertilization rate.However,this effect was not observed after artificial selection intervention through intracytoplasmic sperm injection(ICSI)(P=0.27).In semen,the REEs mixture did not exhibit any significant association with clinical pregnancy.Conclusion Our study revealed a potential association between high La exposure in semen and a decline in fertilization rate,but not clinical pregnancy rate.This is the first to report REEs concentrations in follicular fluid with La,Ce,Pr,and Nd found at significantly lower concentrations than in serum,suggesting that these four REEs may not accumulate in the female reproductive system.However,at the current exposure levels,mixed REEs exposure did not exhibit reproductive toxicity.

In vitro engineered models of neurodegenerative diseases

Neurodegeneration is a catastrophic process that develops progressive damage leading to functional andstructural loss of the cells of the nervous system and is among the biggest unavoidable problems of our age.Animalmodels do not reflect the pathophysiology observed in humans due to distinct differences between the neuralpathways,gene expression patterns,neuronal plasticity,and other disease-related mechanisms in animals andhumans.Classical in vitro cell culture models are also not sufficient for pre-clinical drug testing in reflecting thecomplex pathophysiology of neurodegenerative diseases.Today,modern,engineered techniques are applied to developmulticellular,intricate in vitro models and to create the closest microenvironment simulating biological,biochemical,and mechanical characteristics of the in vivo degenerating tissue.In THIS review,the capabilities and shortcomings ofscaffold-based and scaffold-free techniques,organoids,and microfluidic models that best reflect neurodegeneration invitro in the biomimetic framework are discussed.

Skin care efficacy study of recombinant humanized collagen based on in vitro level

Studying the skin care efficacy of recombinant humanized collagen based on in vitro level.The stability of the recombinant humanized collagen was first analyzed by treating at different temperatures,then its skincare efficacy based on in vitro level was evaluated by detecting the inhibition rate of elastase,the inhibition rate of collagenase,the protein content of type I collagen in human fibroblasts,the inhibition of reactive oxygen species(ROS)with human keratinocytes,and the effects of the recombinant humanized collagen on the expression of hyaluronic acid(HA),filaggrin(FLG)and transglutaminase 1(TGM1)in keratinocytes.The results showed that recombinant humanized collagen was able to maintain stability at temperatures below 70℃.With regard to its skincare efficacy,recombinant humanized collagen could inhibit elastase and collagenase activities and promote the increase of type I collagen content in human fibroblasts.It also showed good inhibition of ROS in keratinocytes in vitro and could increase the expression of HA,FLG,and TGM1 in keratinocytes.In short,the recombinant humanized collagen exhibited a favourable skin care effect in vitro level.This study proved that it has potential firming,anti-wrinkle,moisturizing,and repairing efficacy,and is a valuable cosmetic raw material.