Biological scaffold as potential platforms for stem cells:Current development and applications in wound healing

Wound repair is a complex challenge for both clinical practitioners and researchers.Conventional approaches for wound repair have several limitations.Stem cell-based therapy has emerged as a novel strategy to address this issue,exhibiting significant potential for enhancing wound healing rates,improving wound quality,and promoting skin regeneration.However,the use of stem cells in skin regeneration presents several challenges.Recently,stem cells and biomaterials have been identified as crucial components of the wound-healing process.Combination therapy involving the development of biocompatible scaffolds,accompanying cells,multiple biological factors,and structures resembling the natural extracellular matrix(ECM)has gained considerable attention.Biological scaffolds encompass a range of biomaterials that serve as platforms for seeding stem cells,providing them with an environment conducive to growth,similar to that of the ECM.These scaffolds facilitate the delivery and application of stem cells for tissue regeneration and wound healing.This article provides a comprehensive review of the current developments and applications of biological scaffolds for stem cells in wound healing,emphasizing their capacity to facilitate stem cell adhesion,proliferation,differentiation,and paracrine functions.Additionally,we identify the pivotal characteristics of the scaffolds that contribute to enhanced cellular activity.

Novel mutation of SPG4 gene in a Chinese family with hereditary spastic paraplegia:A case report

BACKGROUND Hereditary spastic paraplegia(HSP)is a group of neurogenetic diseases of the corticospinal tract,accompanied by distinct spasticity and weakness of the lower extremities.Mutations in the spastic paraplegia type 4(SPG4)gene,encoding the spastin protein,are the major cause of the disease.This study reported a Chinese family with HSP caused by a novel mutation of the SPG4 gene.CASE SUMMARY A 44-year-old male was admitted to our hospital for long-term right lower limb weakness,leg stiffness,and unstable walking.His symptoms gradually worsened,while no obvious muscle atrophy in the lower limbs was found.Neurological examinations revealed that the muscle strength of the lower limbs was normal,and knee reflex hyperreflexia and bilateral positive Babinski signs were detected.Members of his family also had the same symptoms.Using mutation analysis,a novel heterozygous duplication mutation,c.1053dupA,p.(Gln352Thrfs*15),was identified in the SPG4 gene in this family.CONCLUSION A Chinese family with HSP had a novel mutation of the SPG4 gene,which is autosomal dominant and inherited as pure HSP.The age of onset,sex distribution,and clinical manifestations of all existing living patients in this family were analyzed.The findings may extend the current knowledge on the existing mutations in the SPG4 gene.

The anti-proliferative activity and cellular antioxidant activity of oenothein B and its content in different Eucalyptus species and region

The leaves of Eucalyptus are abundant in natural resources as a novel potential antioxidant and have broad market prospect.Four of characteristic hydrolysable tannins from Eucalyptus leaves have been demonstrated great application potential as natural antioxidants in our previous research.In this study,the bioactive activities of another hydrolysable tannin isolated and identified as oenothein B(OEB)were evaluated.Content of bioactive compound(hydrolysable tannin)from different Eucalyptus species and regions in southern China were investigated.The results showed that OEB not only exerted anti-proliferative activity against HepG2 cell,but also showed higher cellular antioxidant activity than some common antioxidants.Generally,content of characteristic hydrolysable tannins decreased in the order of OEB>tellimagrandin I(T1)>pedunculagin>gemin D>pentagalloyl glucose(PGG).E.grandis×E.urophylla GL9 and E.urophylla×E.grandis could be recommended as new natural sources to exploit hydrolysable tannins because of high content,widely plantation and strong adaptability.This study supplied first insight on introduction of high cellular antioxidant activity of OEB and selecting the species and region to exploit natural antioxidants.It will promote the increasing of economic value of Eucalyptus.

Comparison of social interaction and neural activation in the main olfactory bulb and the accessory olfactory bulb between Microtus mandarinus and Microtus fortis

To gain insight into the function of AOB and MOB during different social interaction and in different vole species,the behaviors and neural activation of the olfactory bulbs in social interactions of mandarin voles Microtus mandarinus and reed voles Microtus fortis were compared in the present research.Mandarin voles spent significantly more time attacking and sniffing their opponents and sniffing sawdust than reed voles.During same sex encounters,mandarin voles attacked their opponents for a significantly longer time and sniffed its opponent for shorter time compared with male-female interactions.However,no significant behavioral differences were found during encounters of two individual reed voles,regardless of gender composition of the pair.Using c-Fos as an indicator of neural activation,we observed that neural activation was significantly higher in almost all sub-regions of the main olfactory bulb(MOB)and the accessory olfactory bulb(AOB)of mandarin voles compared with reed voles.Numbers of c-Fos-ir neurons in almost all sub-regions of the AOB and the MOB during male-female interactions were also higher than those in interactions of the same sex.Anterior-posterior ratios of Fos-ir neurons in the AOBM(AOBMR)and the AOBG(AOBGR)in male-female interaction were significantly higher than those in interaction of the same sex.The AOBMR of male mandarin voles and reed voles were larger than those of females in male-female interactions.Behavioral patterns are consistent with cellular activity patterns.Consistent level of neural activation in MOB and AOB suggests important roles of both the main olfactory bulb and the accessory olfactory bulb in social interaction in two species.

Sesquiterpenes and polyphenols with glucose-uptake stimulatory and antioxidant activities from the medicinal mushroom Sanghuangporus sanghuang

A chemical investigation on the fermentation products of Sanghuangporus sanghuang led to the isolation and identification of fourteen secondary metabolites(1-14)including eight sesquiterpenoids(1-8)and six polyphenols(9-14).Compounds1-3 were sesquiterpenes with new structures which were elucidated based on NMR spectroscopy,high resolution mass spectrometry(HRMS)and electronic circular dichroism(ECD)data.All the isolates were tested for their stimulation effects on glucose uptake in insulin-resistant HepG2 cells,and cellular antioxidant activity.Compounds 9-12 were subjected to molecular docking experiment to primarily evaluate their anti-coronavirus(SARS-CoV-2)activity.As a result,compounds 9-12 were found to increase the glucose uptake of insulin-resistant HepG2 cells by 18.1%,62.7%,33.7%and 21.4%at the dose of 50μmol·L^(-1),respectively.Compounds 9-12 also showed good cellular antioxidant activities with CAA_(50)values of 12.23,23.11,5.31 and 16.04μmol·L^(-1),respectively.Molecular docking between COVID-19 M^(pro)and compounds 9-12 indicated potential SARS-CoV-2 inhibitory activity of these four compounds.This work provides new insights for the potential role of the medicinal mushroom S.sanghuang as drugs and functional foods.

High affinity soluble ILT2 receptor:a potent inhibitor of CD8^(+)T cell activation

Using directed mutagenesis and phage display on a soluble fragment of the human immunoglobulin superfamily receptor ILT2(synonyms:LIR1,MIR7,CD85j),we have selected a range of mutants with binding affinities enhanced by up to 168,000-fold towards the conserved region of major histocompatibility complex(MHC)class I molecules.Produced in a dimeric form,either by chemical cross-linking with bivalent polyethylene glycol(PEG)derivatives or as a genetic fusion with human IgG Fc-fragment,the mutants exhibited a further increase in ligand-binding strength due to the avidity effect,with resident half-times(t1/2)on the surface of MHC I-positive cells of many hours.The novel compounds antagonized the interaction of CD8 co-receptor with MHC I in vitro without affecting the peptide-specific binding of T-cell receptors(TCRs).In both cytokine-release assays and cell-killing experiments the engineered receptors inhibited the activation of CD8^(+)cytotoxic T lymphocytes(CTLs)in the presence of their target cells,with subnanomolar potency and in a dose-dependent manner.As a selective inhibitor of CD8^(+)CTL responses,the engineered high affinity ILT2 receptor presents a new tool for studying the activation mechanism of different subsets of CTLs and could have potential for the development of novel autoimmunity therapies.