AIM:To investigate the mechanism of reduced tear secretion in depression-related dry eye rats based on 5-HT/TRPV4/AQP5.METHODS:Healthy SD male rats were established with chronic unpredictable mild stress(CUMS)method to establish a depression-induced dry eye model(n=8), and the control group was blank rats(n=8). The ELISA method was used to compare the 5-hydroxytryptamine(5-HT)in serum and hippocampal tissue of the two groups, and the HE sections of lacrimal gland and AQP5 immunohistochemistry were observed. Western blot and RT-PCR were used to detect the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland tissue of the two groups of rats.RESULTS:The tear secretion in the depression-induced group was significantly reduced(P=0.001), the serum and hippocampal 5-HT levels were significantly reduced(all P<0.05), the expression of AQP5 antibody in the lacrimal gland immunohistochemistry was significantly lower than that in the control group(P<0.001), the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland was significantly reduced(all P<0.05), and no obvious inflammatory cells were found in the lacrimal gland tissue sections.CONCLUSION:Depression-related dry eye may occur through a non-inflammatory 5-HT/TRPV4/AQP5 mechanism.

AIM:To investigate the mechanism of reduced tear secretion in depression-related dry eye rats based on 5-HT/TRPV4/AQP5.METHODS:Healthy SD male rats were established with chronic unpredictable mild stress(CUMS)method to establish a depression-induced dry eye model(n=8), and the control group was blank rats(n=8). The ELISA method was used to compare the 5-hydroxytryptamine(5-HT)in serum and hippocampal tissue of the two groups, and the HE sections of lacrimal gland and AQP5 immunohistochemistry were observed. Western blot and RT-PCR were used to detect the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland tissue of the two groups of rats.RESULTS:The tear secretion in the depression-induced group was significantly reduced(P=0.001), the serum and hippocampal 5-HT levels were significantly reduced(all P<0.05), the expression of AQP5 antibody in the lacrimal gland immunohistochemistry was significantly lower than that in the control group(P<0.001), the expression of 5-HT3R, TRPV4 and AQP5 in the lacrimal gland was significantly reduced(all P<0.05), and no obvious inflammatory cells were found in the lacrimal gland tissue sections.CONCLUSION:Depression-related dry eye may occur through a non-inflammatory 5-HT/TRPV4/AQP5 mechanism.

Objective To explore the effective induction scheme for differentiation of adipose-derived mesenchymal stem cell (ADMSC) to insulin producing cell (IPC). Methods Different schemes of small molecule compound were used to induce the differentiation of ADMSC. The purity of cells was analyzed by flow cytometry and the morphological changes of cells were observed under the microscope. The quality, performance and insulin related indicators of cells were detected by hematoxylin-eosin and immunohistochemical staining. The maturity and activity of cells were detected by dithizone (DTZ) and diacetylfluorescein/propidium iodide staining. The induction effect of ADMSC differentiated into IPC was analyzed. Results The purity of ADMSC reached more than 99%, and the sphere forming properties of schemes Ⅰ, Ⅱ and Ⅲ were good. Cell induction mass, the expression effects of pancreatic and duodenal homeobox 1 (PDX1), musculoaponeurotic fibrosarcoma oncogene homolog A (MAFA) and insulin and C peptide of schemes Ⅰ were both better than those of other schemes. The DTZ staining depth may be related to IPC maturity, among which the number of apoptotic cells in scheme Ⅰ was significantly less than that of scheme Ⅱ and Ⅲ. Conclusions Induction scheme Ⅰ may improve the differentiation efficiency of ADMSC to IPC and lay a certain foundation for future clinical IPC transplantation applications.

Dry eye disease is a multifactorial chronic ocular surface disorder that is challenging to manage because its pathogenesis is not well understood. The gut-eye axis theory provides insights into its pathogenesis to guide prevention and treatment. Intestinal flora dysbiosis induces dry eye disease through complex mechanisms involving inflammation, ocular surface microbiota, nerve damage, and microbial metabolites. This article reviews the immunometabolic regulation of the gut-eye axis and summarizes gut flora-targeted interventions(fecal microbiota transplantation, probiotic supplementation, and dietary modification)to provide a theoretical basis for dry eye disease prevention and treatment.

Objective:To investigate whether ultra-high dose rate (FLASH) irradiation can reduce radiation-induced intestinal injuries of mice compared to conventional dose rate (CONV) irradiation.Methods:Both FLASH and CONV irradiation were delivered with electron beam, with dose rates of 750 Gy/s and 0.5G y/s, respectively. A total of 105 mice were randomly divided into groups using a simple randomization method. Twenty-one mice were selected for weight observation, 7 mice in each group. After 9 Gy FLASH and CONV irradiation on the abdomen, the weight changes of mice were measured every other day, and compared among three groups. Twenty-four mice were selected for pathological examination including 5 mice in the control group. Three-and-a-half-day days after 12 Gy FLASH ( n=10) and CONV irradiation ( n=9) on the abdomen, the intestines of the mice were taken. Pathological sections were stained with hematoxylin-eosin (HE) to compare the number and percentage of regenerated crypts of the small intestine between two groups. After 12 Gy FLASH ( n=10) and CONV irradiation ( n=10) on the abdomen, the survival of 20 mice was observed. After FLASH using 4.5 Gy×2 times ( n=10) and CONV irradiation at 9 Gy×1 time ( n=10) on the abdomen, the weight changes were observed. After FLASH using 6 Gy×2 times ( n=10) and CONV irradiation at 12 Gy×1 time ( n=10) on the abdomen, the survival of mice was observed. The time interval between two irradiation was 1 min. EBT3 film was employed to monitor the actual exposure dose of the mice. The variables conforming to normal distribution were expressed by Mean±SD. Inter group comparison was performed by independent t-test. The survival of mice among different groups was compared by log-rank test. Results:After 9 Gy of abdominal irradiation, the mean weight of mice in the FLASH group was significantly higher than that in the CONV group. The weight of mice in the FLASH and CONV groups was (19.8±0.8) g and (18.0±1.8)g ( P=0.036) at 7 days after irradiation, (22.0±1.0)g and (21.2±0.5)g ( P=0.075) at 15 days after irradiation, and (24.2±1.4)g and (22.0±1.2)g ( P=0.012) at 25 days after irradiation, respectively. After 12 Gy irradiation, the mean survival of mice in FLASH and CONV groups was 4 days and 4.7 days ( P=0.029). After 12 Gy total abdominal irradiation, the mean number of intestinal regenerative crypts in the FLASH and CONV groups was 2.9/mm and 1.2/mm ( P=0.041), and the percentage of intestinal regenerative crypts was 34.1% and 14.1%, respectively. The survival of mice irradiated by FLASH using 6 Gy×2 times was longer compared with that of mice after CONV irradiation at 12 Gy×1 time. The weight of mice after 4.5 Gy×2 times irradiation was higher than that of mice after CONV irradiation at 9 Gy×1 time. Conclusion:Weight, survival and the number of intestinal regenerative crypts in the FLASH group are higher than those in the CONV group after irradiation, indicating that radiation-induced intestinal injury caused by FLASH irradiation is slighter than that of CONV irradiation.

Objective To observe the effect of electroacupuncture on corneal Toll-like receptor 4(TLR4)-mediated inflammatory signaling pathway in diabetic dry eye rats and to explore the mechanism of electroacupuncture in the treat-ment of diabetic dry eye.Methods A type 2 diabetic rat model was established in 32 healthy male Sprague-Dawley(SD)rats by intraperitoneal injection of streptozotocin(30 mg·kg-1)for 12 weeks after feeding with high-sugar and high-fat di-et for 4 weeks.Twenty-five successfully modeled diabetic dry eye rats were randomly divided into the model group(non-in-tervention),electroacupuncture group(the"Jingming","Cuanzhu","Sizhukong","Taiyang"and"Tongziliao"acupoints were treated with acupuncture,and then"Cuanzhu"and"Tongzilao"acupoints were treated with electroacupuncture,15 min for each time,once a day),sham acupuncture group(blunt-tip needle pricking was performed at the same acupoints as the electroacupuncture group),and fluorometholone group(1 g·L-1fluorometholone eye drops were used in both eyes at 8 o'clock,13 o'clock,and 18 o'clock,1 drop each time),with 6 rats in each group,lasting for 2 weeks.Another 6 healthy male SD rats were selected as a blank group.Random blood glucose,tear film breakup time(BUT),tear secre-tion,corneal fluorescein staining(FL)score,and corneal touch threshold(CTT)of rats in each group were detected be-fore modeling,after modeling,and after the intervention.Hematoxylin and Eosin(HE)staining was performed to observe the corneal morphologic changes in each group.Immunofluorescence histochemical staining was adopted to detect the cor-neal TLR4-positive expression in each group.The TLR4,phosphorylated nuclear factor-kappa P65(P-NF-KB P65),inter-leukin(IL)-1β,and IL-18 expression levels in the cornea were detected by Western blot.Results After modeling,com-pared with the blank group,BUT,tear secretion and CTT decreased and FL increased in all experimental groups,and the differences were statistically significant(all P＜0.01).After the intervention,compared with the model group,FL de-creased,and BUT,tear secretion and CTT increased in the electroacupuncture group,and the differences were statistically significant(all P＜0.05).Corneal HE staining showed that after the intervention,the corneal surface of rats in the model group and sham acupuncture group was not smooth,and the corneal epithelial cells were thickened and disorganized;the corneal surface of rats in the electroacupuncture group and fluorometholone group was smooth,and the corneal epithelial cells were arranged neatly.After the intervention,compared with the blank group,the corneal TLR4 expression of rats in all other groups was elevated,and the differences were statistically significant(all P＜0.05);compared with the model group,the corneal TLR4 expression of rats in the electroacupuncture group and fluorometholone group was reduced(both P＜0.01).Compared with the blank group,corneal TLR4,P-NF-κBP65,IL-1β and IL-18 protein expressions increased in the model group and sham acupuncture group(all P＜0.05);compared with the model group,these expressions decreased in the electroacupuncture group and the fluorometholone group(all P＜0.05).Conclusion Electroacupuncture can im-prove the ocular surface signs and inhibit the expressions of TLR4,P-NF-κB P65,IL-1 β,and IL-18 in the cornea of type 2 diabetic dry eye rats,and its mechanism of action may be related to the regulation of TLR4-mediated inflammatory signaling pathway,which inhibits ocular surface inflammation in diabetic dry eye rats.

Objective To investigate the effect of acupuncture on the morphology of the dry eye rabbit's cornea and the nuclear factor κB(NF-κB)signaling pathway of the corneal tissue to analyze the mechanism of acupuncture on dry eyes.Methods Twenty-four healthy New Zealand rabbits,without restriction on sex,were randomly divided into four groups,including a blank group,a model group,an acupuncture group,and a sham acupuncture group,with 6 in each group.Rabbits in the blank group were not treated;rabbits in the other three groups were treated with scopolamine hydro-bromide 2.0 mg·kg-1 by subcutaneous injection at 8:00,11:00,14:00 and 18:00 each day for 35 consecutive days un-til the end of the experiment.Rabbits in the sham acupuncture group were treated with sham acupuncture on the 22nd day after successful modeling by quickly pricking acupoints(Jingming BL1,Cuanzhu BL2,Sizhukong SJ23,Taiyang EX-HN5 and Tongziliao GB1)with a blunt acupuncture needle,once a day,for a total of 14 days.Rabbits in the acupuncture group were treated with acupuncture at the same acupoints as the sham acupuncture group after successful modeling.The corneal fluorescence staining was conducted on Days 0,21,28 and 35 after modeling.On Day 35,corneal confocal microscope ex-aminations were conducted.Then,the rabbits were sacrificed,the corneal morphological changes were observed by light microscope and transmission electron microscope,and the expression of corneal NF-κB protein was detected by Western blot.Results Compared with the model group,the score of rabbit corneal fluorescein staining in the acupuncture group and blank group decreased on the 28th and 35th days after modeling,and the differences were statistically significant(all P＜0.05).The results of the confocal microscope examination on Day 35 after modeling showed that,compared with other groups,there were a large number of globular immune cells and activated stromal cells with unclear boundaries and irregu-lar sizes in the stromal layer and inflammation in the area with irregular intercellular space in the model group and the sham acupuncture group.In the acupuncture group,the morphology of stromal layer cells improved,the cells were slightly acti-vated,and there were no obvious abnormalities in the corneal nerve morphology.On the 35th day after modeling,the re-sults of the light microscope showed that,the surface of the corneal tissue in the model group and the sham acupuncture group showed hyperkeratinized flat epithelial cells,lymphocyte infiltration,increased number of focal epithelial cell layers,and epithelial cell detachment.In the acupuncture group,there were 4-6 layers of epithelial cells in the corneal epitheli-um,and epithelial shedding decreased.In addition,the lymphocyte infiltration decreased compared with the model group.On the 35th day after modeling,the results of the transmission electron microscope showed that abnormal microvilli oc-curred and epithelial cells were absent in the corneal epithelial cells of rabbits in the model group and the sham acupuncture group,the cell space was widened,the rough endoplasmic reticulum was severely expanded,and desmosomes were dis-banded with mitochondrial swelling.In the acupuncture group,the microvilli structure of epithelial cells was sparse and short,local deletion was still observed,the rough endoplasmic reticulum was slightly expanded,and no obvious swelling of mitochondria was observed.On the 35th day after modeling,the Western blot examination results showed that,compared with the blank group,the expression of p-NF-κB p65 was up-regulated in both the model group and sham acupuncture group(both P＜0.05);compared with the model group and sham acupuncture group,the expression of p-NF-κB p65 in the acupuncture group was down-regulated(both P＜0.05).Conclusion Acupuncture can inhibit the NF-κB signaling path-way to play an anti-inflammatory role and relieve corneal inflammation and injury of dry eye rabbit models.

Objective To reveal the potential mechanism of electroacupuncture regulating the neuroinflammatory signaling pathway mediated by triggering receptor expressed on myeloid cells 2(TREM2)in trigeminal ganglion(TG)and caudate nucleus of spinal trigeminal nucleus(SpVc)of rats with type 2 diabetes and dry eyes and alleviating ocular surface sensory abnormalities.Methods Healthy male Sprague-Dawley(SD)rats were induced by intraperitoneal injection of 10 g·L-1 streptozotocin to establish a type 2 diabetes dry eye rat model after 4 weeks of high-glucose and high-fat diets.In the 12th week of the experiment,successfully modeled rats were randomly divided into the model group,electroacupunc-ture group,sham-acupuncture group and fluorometholone group,and healthy male SD rats fed with normal diets were se-lected as the blank group.Rats in all groups were intervened for 2 weeks.The corneal fluorescein sodium staining(FL),tear secretion[detected by phenol red thread(PRT)test],tear film break-up time(BUT),and corneal touch threshold(CTT)in each group were measured before,after modeling,and after the intervention.The changes in tissue morphology of TG and SpVc and TREM2 positive expression sites in each group were observed.The messenger ribonucleic acid(mR-NA)expression of TREM2,interleukin-18(IL-18)and interleukin-1β(IL-1β)of TG and Sp Vc in each group were detec-ted.Results After modeling,compared with the blank group,the FL scores of rats significantly increased and PRT,BUT and CTT significantly decreased in other groups(all P＜0.01).After the intervention,compared with the model group,the electroacupuncture group and fluorometholone group showed significant reductions in FL scores and significant increases in PRT,BUT and CTT(all P＜0.01);there was no statistically significant difference in these indicators in the sham-acupuncture group(all P＞0.05).Compared with the electroacupuncture group,the PRT and CTT of rats in the flu-orometholone group and sham-acupuncture group were significantly reduced,the FL score significantly increased and BUT significantly decreased in the sham-acupuncture group(all P＜0.01),and there was no statistically significant difference in FL score and BUT of rats in the fluorometholone group(both P＞0.05).Compared with the sham-acupuncture group,the fluorometholone group showed a decrease in FL score and an increase in PRT,BUT and CTT in rats,with statistically dif-ferent significances(all P＜0.05).The immunofluorescence double-labeling assay showed a positive expression of TREM2 in activated microglia of TG and SpVc in the model group.The reverse transcription-polymerase chain reaction of TG and SpVc showed that compared with the blank group,the TREM2 mRNA expression in the TG and SpVc of the model group,electroacupuncture group,fluorometholone group and sham-acupuncture group decreased,the IL-18 and IL-1β mRNA in TG and SpVc of the model group,IL-18 and IL-1β mRNA in TG and IL-1β mRNA in SpVc of the sham-acupuncture group increased(all P＜0.05);compared with the model group,the TREM2 mRNA expression increased and IL-18 and IL-1β mR-NA expression decreased in the TG and SpVc of the electroacupuncture group and fluorometholone group(all P＜0.05).Compared with the electroacupuncture group,the TREM2 mRNA expression decreased and IL-18,IL-1β mRNA expression increased in TG and SpVc of the sham-acupuncture group(all P＜0.05),and no significant difference was found in TREM2,IL-18 and IL-1β mRNA expression in TG and SpVc of the fluorometholone group(all P＞0.05).Compared with the sham-acupuncture group,the TREM2 mRNA expression in TG and SpVc increased in the fluorometholone group,while the IL-18 mRNA expression in SpVc decreased(all P＜0.05);the IL-1β mRNA in TG and SpVc and the IL-18 mRNA in TG of the fluorometholone group showed no statistically significant difference(all P＞0.05).Conclusion Electroacupunc-ture can effectively alleviate the ocular surface sensory abnormalities of rats with type 2 diabetes and dry eyes by regulating the inflammatory signaling pathway mediated by TREM2 in TG and SpVc.

Dry eye is a common chronic ocular surface disease in ophthalmology.Its pathogenesis is still not fully clar-ified,and there has been no effective prevention and treatment strategy.In recent years,with the booming development of molecular biology technologies such as gene chip technology and transcriptome sequencing technology,transcriptomic re-search on the dry eye has made some progress.In this article,we review the application of transcriptomics in dry eye re-search and explore the pathogenesis of dry eye with a view to providing new ideas for the clinical treatment of dry eye and potential targets for the development of new drugs for dry eye.

Dry eye disease(DED)refers to a condition characterized by reduced stability of the tear film or an imbalance in the microenvironment of the ocular surface, resulting from abnormalities in quality, quantity and kinetics of tear. This condition leads to various ocular discomforts and even visual impairment. The pathogenesis of DED is multifactorial and current treatment mainly focuses on symptom relief and preservation of visual function. Acupuncture has shown effectiveness in treating dry eye, although its underlying mechanism remains incompletely understood. Proteomics technology offers a comprehensive and systematic approach to studying the functions, structures and interactions of proteins. Its application in DED research can provide valuable insights into the dynamic changes in protein levels associated with different etiology or the course of DED and facilitate the identification of potential biomarkers. Furthermore, proteomics can systematically explore the regulatory mechanisms underlying acupuncture treatment for DED, providing a theoretical basis for acupuncture treatment research and contributing to the understanding of its effects at a fundamental level. This paper aims to explore the potential application of proteomics in both clinical and basic research on DED. Ultimately, it strives to offer scientific and effective strategies for the diagnosis and treatment of DED and advance our knowledge of the mechanisms underlying acupuncture therapy.