Olfactory receptors (ORs) form the largest superfamily of G protein-coupled receptors (GPCRs). Traditionally recognized for their role in the nasal olfactory epithelium, where they mediate the sense of smell, accumulating evidence has firmly established their ectopic expression in non-olfactory tissues, including the intestine, lungs, and kidneys. The intestine, as the primary site for nutrient digestion and absorption, harbors a highly complex chemical environment. To adapt to this environment, the gut employs a sophisticated network of “chemosensors” to monitor luminal contents and maintain homeostasis. Among these sensors, intestinal ORs have emerged as crucial functional components, serving as a molecular bridge that connects environmental chemical signals—such as food-derived odorants—to specific physiological responses. This discovery has significantly deepened our understanding of how dietary flavors and compounds influence intestinal physiology at the molecular level. This review systematically summarizes the expression profiles, ligand classification, and biological functions of ORs within the gastrointestinal tract. Studies indicate that intestinal ORs exhibit distinct spatial distribution patterns across different gut segments and display cell-type specificity, particularly within enterocytes and enteroendocrine cells. These receptors function as versatile sensors capable of recognizing a wide variety of ligands, including exogenous dietary components, gut microbiota metabolites such as short-chain fatty acids, and endogenous small molecules like azelaic acid. Upon activation by specific ligands, intestinal ORs trigger intracellular signaling cascades, primarily involving the AC-cAMP-PKA pathway or calcium influx channels. A major focus of this review is to elucidate the molecular mechanisms by which these receptors regulate the secretion of gut hormones. Activation of specific ORs in enteroendocrine cells has been shown to stimulate the release of hormones such as glucagon-like peptide-1 (GLP-1), peptide YY (PYY), and serotonin (5-HT), thereby modulating systemic energy metabolism, glucose homeostasis, and gastrointestinal motility. Furthermore, the review addresses the critical roles of ORs in immune regulation and pathology. Evidence suggests that specific ORs contribute to the maintenance of intestinal immune homeostasis and may offer protection against inflammation. Beyond their involvement in inflammatory responses, ORs such as Olfr78 have been shown to regulate the differentiation and function of intestinal endocrine cells. Similarly, Olfr544 has been demonstrated to alleviate intestinal inflammation by remodeling the gut microbiome and metabolome. These findings collectively suggest that specific ORs hold promise as therapeutic targets for mitigating intestinal inflammation and maintaining gut homeostasis. Additionally, the review explores the emerging role of ORs in cancer. Although OR expression is often downregulated in tumor tissues compared to normal mucosa, activation of specific ORs by certain ligands can inhibit tumor cell proliferation and migration and induce apoptosis via pathways such as MEK/ERK and p38 MAPK. Conversely, other receptors, such as OR7C1, may serve as biomarkers for cancer-initiating cells. In conclusion, intestinal ORs represent a vital component of the gut’s sensory network. The review also discusses the translational potential of these findings. By elucidating the precise pairing relationships between dietary components and specific ORs, novel therapeutic strategies could be developed. Intestinal ORs may thus emerge as promising targets for nutritional and pharmacological interventions in metabolic diseases, inflammatory bowel diseases, and malignancies.

BACKGROUND:Traditional bone tissue engineering techniques for treating critical bone defects suffer from low osteogenic efficiency and poor safety.Gene-enhanced bone tissue engineering grafts constructed with non-viral nanoparticles have attracted widespread attention from scholars both domestically and internationally due to their higher osteogenic rates and safety,leading to extensive research in this field.OBJECTIVE:To review new technologies,methods,and challenges in the research of nanoparticles in gene therapy for bone tissue engineering,aiming to provide a reference for research on gene therapy mediated by nanoparticles in bone tissue engineering.METHODS:The first author searched PubMed,Web of Science,and CNKI.The Chinese and English search terms were"bone defect repair,bone tissue engineering,gene delivery,nanoparticles,non-viral gene vector,sustained release technology,sequential release,targeted delivery."Finally,84 articles were included for summary.RESULTS AND CONCLUSION:(1)Targeted gene delivery at various physiological stages of bone defect healing can significantly enhance bone repair efficacy.In the early inflammatory stage,delivering anti-inflammatory genes via nanoparticles to regulate the inflammatory response lays the foundation for subsequent bone healing.During the angiogenesis phase,local delivery of vascularization target genes aids in forming a highly organized vascular system,significantly accelerating bone healing.As vascularization progresses,neural re-innervation of the bone begins;at this stage,delivering functional genes promoting nerve regeneration facilitates neuro-osteogenic regeneration.During the osteogenic phase,constructing nanoparticle-bone gene complexes directly enhances the efficiency of bone formation on scaffold and in vivo.(2)Non-viral nanocarriers such as various organic and inorganic nanoparticles,metal-organic frameworks,and exosomes show immense potential in gene therapy for bone tissue engineering.Each of these carriers has its unique advantages and limitations.Therefore,in practical applications,selection of the appropriate type primarily depends on factors such as gene transfection efficiency,biocompatibility,and osteogenic properties.(3)To comprehensively improve the efficiency of gene delivery,the gene transfection efficiency of nanocarriers is mainly enhanced through various functional designs,including enhancing the temporal regulation ability such as slow release and multi-gene delivery sequence,enhancing the spatial targeting ability of bone tissue and osteoblast-related cells,enhancing the transmembrane transport efficiency and nuclear targeting ability.(4)Numerous challenges need to be overcome in order to further promote the clinical application of nanoparticle-mediated gene therapy for bone tissue engineering,including improving gene transfection efficiency of organic carriers,reducing biosafety risks of inorganic carriers,optimizing the production process of new types of nanocarriers,and promoting interactions between other physiological processes and osteogenesis.These are also research hotspots and trends of gene therapy for bone tissue engineering in the future.

Aim To investigate the effect of linarin on improving cognitive behavior of APP/PS1 mice,and to explore the therapeutic effect of linarin on A β deposi-tion and neuroinflammation and its correlation.Meth-ods APP/PS1 transgenic mice were randomly divid-ed into the model group,high-dose group,medium-dose group,low-dose group and positive control group.C57BL/6J mice were set as the normal group.Morris water maze was used to evaluate the learning and mem-ory abilities of mice.TUNEL staining was used to de-tect the apoptosis of neurons in the CA1 region of mice.IHC was used to detect the expression levels of Aβ42 and GFAP.Western blot was used to detect the expression levels of BACE1 and PS-1.Results Com-pared with the normal group,mice of the model group showed lower NCP,shorter target quadrant travel,less target quadrant residence time percentage(all P＜0.01),higher apoptosis rate of neurons in the CA1 re-gion(P＜0.01),significantly higher protein expres-sion levels of A β42 and GFAP(all P＜0.01),and significantly higher protein expression levels of BACE1 and PS-1(all P＜0.01).Compared with the model group,the medium-dose group,high-dose group and positive control group showed higher NCP,longer tar-get quadrant travel,more target quadrant residence time percentage(all P＜0.05),lower apoptosis rate of neurons in the CA1 region(P＜0.01),significantly lower protein expression levels of A β42 and GFAP(all P＜0.01),and significantly lower protein expression levels of BACE1 and PS-1(all P＜0.01).Conclu-sions Linarin can inhibit two key enzymes to reduce the decomposition of APP and the generation of A β42,thereby inhibiting the activation of astrocytes,allevia-ting neuroinflammation,improving the core pathologi-cal features of AD,and thus significantly improving learning and memory impairment in APP/PS1 mice.

BACKGROUND:Traditional bone tissue engineering techniques for treating critical bone defects suffer from low osteogenic efficiency and poor safety.Gene-enhanced bone tissue engineering grafts constructed with non-viral nanoparticles have attracted widespread attention from scholars both domestically and internationally due to their higher osteogenic rates and safety,leading to extensive research in this field.OBJECTIVE:To review new technologies,methods,and challenges in the research of nanoparticles in gene therapy for bone tissue engineering,aiming to provide a reference for research on gene therapy mediated by nanoparticles in bone tissue engineering.METHODS:The first author searched PubMed,Web of Science,and CNKI.The Chinese and English search terms were"bone defect repair,bone tissue engineering,gene delivery,nanoparticles,non-viral gene vector,sustained release technology,sequential release,targeted delivery."Finally,84 articles were included for summary.RESULTS AND CONCLUSION:(1)Targeted gene delivery at various physiological stages of bone defect healing can significantly enhance bone repair efficacy.In the early inflammatory stage,delivering anti-inflammatory genes via nanoparticles to regulate the inflammatory response lays the foundation for subsequent bone healing.During the angiogenesis phase,local delivery of vascularization target genes aids in forming a highly organized vascular system,significantly accelerating bone healing.As vascularization progresses,neural re-innervation of the bone begins;at this stage,delivering functional genes promoting nerve regeneration facilitates neuro-osteogenic regeneration.During the osteogenic phase,constructing nanoparticle-bone gene complexes directly enhances the efficiency of bone formation on scaffold and in vivo.(2)Non-viral nanocarriers such as various organic and inorganic nanoparticles,metal-organic frameworks,and exosomes show immense potential in gene therapy for bone tissue engineering.Each of these carriers has its unique advantages and limitations.Therefore,in practical applications,selection of the appropriate type primarily depends on factors such as gene transfection efficiency,biocompatibility,and osteogenic properties.(3)To comprehensively improve the efficiency of gene delivery,the gene transfection efficiency of nanocarriers is mainly enhanced through various functional designs,including enhancing the temporal regulation ability such as slow release and multi-gene delivery sequence,enhancing the spatial targeting ability of bone tissue and osteoblast-related cells,enhancing the transmembrane transport efficiency and nuclear targeting ability.(4)Numerous challenges need to be overcome in order to further promote the clinical application of nanoparticle-mediated gene therapy for bone tissue engineering,including improving gene transfection efficiency of organic carriers,reducing biosafety risks of inorganic carriers,optimizing the production process of new types of nanocarriers,and promoting interactions between other physiological processes and osteogenesis.These are also research hotspots and trends of gene therapy for bone tissue engineering in the future.

Objective:To develop a nutritional management protocol for head and neck cancer (HNC) patients undergoing radiotherapy based on evidence-based methodology, and to evaluate its clinical effectiveness.Methods:Relevant literature on nutritional management in radiotherapy for HNC patients was systematically searched. After evidence extraction, a preliminary protocol was drafted and finalized through expert consensus. The finalized protocol included five timepoints during hospitalization, covering six components and 35 nursing and clinical care items. A quasi-experimental design was adopted. Using convenience sampling, 100 HNC patients admitted to Jinhua Municipal Central Hospital from October 2022 to June 2024 were enrolled. Patients treated between October 2022 and July 2023 formed the control group ( n=50), and those treated from September 2023 to June 2024 comprised the intervention group ( n=50). The control group received routine care, while the intervention group was managed with the evidence-based nutrition protocol. Body weight and nutrition-related laboratory indicators were measured before radiotherapy, at week 4, and at the end of week 6. Results:At week 4 of radiotherapy, the intervention group had a higher lymphocyte count than the control group, with statistically significant differences ( P<0.05). At week 6, total serum protein, serum albumin, and lymphocyte counts were all higher in the intervention group, with statistically significant differences ( P<0.05) . Conclusions:The evidence-based nutritional management protocol developed for HNC patients undergoing radiotherapy effectively improves nutritional status. It provides a valuable reference for healthcare professionals in clinical practice.

Aim To investigate the effects of m6A demethylase ALKBH5 on cardiomyocytes pyroptosis in mice with myocardial infarction(MI).Methods The MI model of left anterior descending coronary artery ligation surgery was established by knocking down ALKBH5 using adeno-associated virus,and the hypox-ia model of mouse cardiomyocytes(HL-1)was estab-lished by knocking down small interfering RNA.The effects of ALKBH5 on the pyroptosis of MI mice and hypoxic HL-1 cells were observed.Subsequently,mechanism studies were conducted at the cellular lev-el,and the binding of ALKBH5 and IGF2BP2 to NL-RP3 mRNA was detected through RNA pull down and RNA immunoprecipitation(RIP)experiments.The MeRIP-qPCR method was used to determine the effects of ALKBH5 on the mRNA m6A level of NLRP3.Acti-nomycin D for RNA stability experiments were conduc-ted to detect the effects of ALKBH5 and IGF2BP2 on the stability of NLRP3 mRNA.Results Knocking down ALKBH5 in vivo and in vitro both inhibited NL-RP3 inflammasome activation and alleviated pyroptosis in MI mice and hypoxic HL-1 cells.Mechanistically,the results showed that NLRP3 mRNA could bind to ALKBH5 protein in HL-1 cells;knocking down ALK-BH5 could increase the m6A level of NLRP3 and re-duce the stability of NLRP3 mRNA;subsequently,it was confirmed that NLRP3 mRNA and IGF2BP2 pro-tein bound to each other;knocking down IGF2BP2 in-creased the mRNA stability of NLRP3.The Rescue ex-periment showed that knocking down IGF2BP2 re-versed the decrease in NLRP3 mRNA expression caused by knocking down ALKBH5.Conclusions ALKBH5 mediated m6A modification of NLRP3 pro-motes cardiomyocytes pyroptosis in mice with myocardi-al infarction.

Objective To investigate the correlation between the change of muscle tissues and bone mineral density(BMD)in elderly women with hip fracture,with consideration of the impact of muscle mechanics on bone mass changes.Methods A total of 79 elderly patients with hip fracture were selected as the fracture group,and 45 physical examination personnel as the control group.The differences in total muscle mass,total body fat,trunk muscle mass,trunk fat mass,arm muscle mass,arm fat mass,leg muscle mass,leg fat mass,as well as BMD at the lumbar spine(L1-4),femoral neck,hip joint,and whole body were analyzed.Results Muscle content and fat content of the whole body,upper limb and lower limb,fat content of the trunk,relative skeletal muscle index(SMI)and BMD of the whole body in fracture group were significantly lower than those in control group(P＜0.05).The incidence rate of sarcopenia for elderly women in fracture group was higher than that in control group.BMD of femoral neck of the affected side was significantly lower than that of the intact side in women with intertrochanteric fractures.Logistic regression analysis found that SMI in elderly women with hip fracture was negatively correlated with age,and positively correlated with body mass index(BMI),BMD of the femoral neck and whole body.Conclusions The rate of sarcopenia was significantly higher in elderly patients with hip fracture,and SMI was closely related to BMD of the femoral neck and whole body.Therefore,sarcopenia should be highly emphasized in the prevention and treatment of osteoporotic fracture in elderly people.

Objective To investigate the role and mechanism of neurotrophin-3(NT-3)in promoting neurological recovery after sep-sis-associated encephalopathy(SAE).Methods Twenty-four Sprague-Dawley(SD)rats were randomly divided into the Sham,SAE,and+NT-3 groups(n=8).Neurological deficits were evaluated using a behavioral scoring system.Western blotting was performed to assess the expression levels of NT-3,S100β,caspase-1,and microtubule-associated protein 1 light chain 3B(LC3B)in brain tissues.Immuno-histochemistry(IHC)was performed to assess interleukin-1 β(IL-1β)expression level.For cellular experiments,groups included normal,lipopolysaccharide(LPS),LPS+NT-3,LPS+NT-3+3-MA(autophagy inhibitor),and LPS+NT-3+compound C(AMPK inhibitor).Western blotting was used to analyze LC3B,NLRP3,ASC,AMPK,phosphorylated AMPK(p-AMPK),mTOR,and phosphorylated mTOR(p-mTOR)expression levels.Caspase-1 expression in cells was evaluated using immunofluorescence(IF).Results NT-3 expression in septic rat brain tissues increased progressively from d1 to d2(P＜0.05).Compared with the SAE group,the SAE+NT-3 group exhibited elevated neurological scores.The expression levels of IL-1β,S100β,and caspase-1 decreased from d1 to d2,while the aurtophagy level increased from d1 to d2(all P＜0.05).In cellular models,the LPS+NT-3 group showed decreased caspase-1 expression and increased autophagy activity compared to that in the LPS group from 1 h to 3 h(P＜0.05).Compared to the LPS+NT-3 group,the LPS+NT-3+3-MA group exhibited elevated NLRP3,ASC,and caspase-1-positive cells(P＜0.05),whereas the LPS+NT-3+Compound C group exhibited reduced p-AMPK,increased p-mTOR,and attenuated autophagy(P＜0.05).Conclusion NT-3 activates autophagy through the AMPK/mTOR signaling pathway during the early phase of SAE,thereby eliminating pyroptosis-associated proteins NLRP3 and ASC to promote neurolog-ical recovery.

Objective To investigate the effect of cordyceps sinensis(CS)on the activation of fibroblasts through IL-6 trans-signaling pathway and its specific mechanism in the treatment of renal fibrosis.Methods Renal fibrosis mouse model was established by unilateral ischemia/reperfusion(UIR),and the mice were administered intragastrically CS,soluble glycoprotein 130 Fc(sgp130Fc)or Hyper-IL-6.Masson's trichrome staining was utilized to identify tubulointerstitial fibrosis.PAS staining was utilized to assess the extent of renal injury.Western blot was employed to analyze the expression levels of fibrosis markers[alpha-smooth muscle actin(α-SMA),fibronectin(FN)]and proteins associated with IL-6 trans-signaling pathway[phosphorylated signal transducer and activator of transcription 3(p-STAT3),soluble interleukin-6 receptor(sIL-6R)].The expression and localization of proteins were additionally detected by immunohistochemistry,immunofluorescence and qPCR.The effect of cordyceps sinensis extract cordycepin on IL-6 trans-signaling in fibroblasts was further investigated in vitro.Results The results from in vivo experiments showed that administration of CS during the chronic phase demonstrated a beneficial protective impact on inflammation and fibrosis in the affected kidney,and serum creatinine levels and collagen deposition were decreased.Western blot analysis revealed a decrease in the expression levels of α-SMA,FN,as well as IL-6 trans-signaling pathway protein p-STAT3,sIL-6R in the treatment group.Additionally,the mRNA expression levels of chemokines monocyte chemoattractant protein-1(MCP-1)and C-X-C motif chemokine ligand 12(CXCL12)were also decreased in the CS treatment group.Additionally,Hyper-IL-6 can partially counteract the therapeutic effects of CS.In vitro experiments further demonstrated that cordycepin inhibited the secretion of IL-6 from NRK-52E.Combined treatment of recombinant IL-6 and sIL-6R protein activated NRK-49F,leading to a significant increase in α-SMA,FN,and p-STAT3 expression levels.Cordycepin or sgp130Fc treatment significantly inhibited the proliferation of fibroblasts induced by IL-6 trans-signaling pathway.Conclusion CS can significantly reduce IL-6 secretion by renal tubular epithelial cells and inhibit the activation of IL-6 trans-signaling pathway in fibroblasts,thereby ameliorating renal interstitial fibrosis.

AIM:To observe the effect of continuous light on the structure and differential metabolites of gut microbiota in mice.METHODS:The mice were randomly divided into normal light(light/dark,LD)group and 24-hour continuous light(light/light,LL)group.The body weight,fasting blood glucose,serum free fatty acids,serum triacylglycerol and serum total cholesterol levels of each group of mice were measured after 10 weeks.Fresh feces were collected,and 16S rRNA sequencing technology was used to study the effect of continuous light on the diversity,structure,and species composition of gut microbiota in mice.Additionally,liquid chromatography-mass spectrometry(LC-MS)analysis was per-formed to observe the effect of continuous light on the metabolites in mice.RESULTS:Compared with the LD group,the body weight,fasting blood glucose and lipid levels of the LL group were increased(P＜0.05).At the phylum level,the proportion of Firmicutes in the LL group increased,while the proportion of Bacteroidetes decreased.At the class level,the abundance of norank_f_Muribaculaceae and Prevotellaceae_UCG-001 in the LL group decreased significantly,while the abundance of Lactobacillus,Turicibacter and Odoribacter increased significantly.Non-targeted metabolomics analysis iden-tified 65 and 73 differential metabolites under positive and negative modes,involving six major metabolic pathways,in-cluding ABC transporters,purine metabolism,pyrimidine metabolism,secondary bile acid biosynthesis,protein digestion and absorption,and choline metabolism in cancer.CONCLUSION:The structure and metabolites of gut microbiota in mice exposed to continuous light are relatively specific,and inosine may be a key biomarker and potential therapeutic tar-get for biological clock disorders.