Circadian rhythm is an endogenous biological clock mechanism that enables organisms to adapt to the earth’s alternation of day and night. It plays a fundamental role in regulating physiological functions and behavioral patterns, such as sleep, feeding, hormone levels and body temperature. By aligning these processes with environmental changes, circadian rhythm plays a pivotal role in maintaining homeostasis and promoting optimal health. However, modern lifestyles, characterized by irregular work schedules and pervasive exposure to artificial light, have disrupted these rhythms for many individuals. Such disruptions have been linked to a variety of health problems, including sleep disorders, metabolic syndromes, cardiovascular diseases, and immune dysfunction, underscoring the critical role of circadian rhythm in human health. Among the numerous systems influenced by circadian rhythm, the skin—a multifunctional organ and the largest by surface area—is particularly noteworthy. As the body’s first line of defense against environmental insults such as UV radiation, pollutants, and pathogens, the skin is highly affected by changes in circadian rhythm. Circadian rhythm regulates multiple skin-related processes, including cyclic changes in cell proliferation, differentiation, and apoptosis, as well as DNA repair mechanisms and antioxidant defenses. For instance, studies have shown that keratinocyte proliferation peaks during the night, coinciding with reduced environmental stress, while DNA repair mechanisms are most active during the day to counteract UV-induced damage. This temporal coordination highlights the critical role of circadian rhythms in preserving skin integrity and function. Beyond maintaining homeostasis, circadian rhythm is also pivotal in the skin’s repair and regeneration processes following injury. Skin regeneration is a complex, multi-stage process involving hemostasis, inflammation, proliferation, and remodeling, all of which are influenced by circadian regulation. Key cellular activities, such as fibroblast migration, keratinocyte activation, and extracellular matrix remodeling, are modulated by the circadian clock, ensuring that repair processes occur with optimal efficiency. Additionally, circadian rhythm regulates the secretion of cytokines and growth factors, which are critical for coordinating cellular communication and orchestrating tissue regeneration. Disruptions to these rhythms can impair the repair process, leading to delayed wound healing, increased scarring, or chronic inflammatory conditions. The aim of this review is to synthesize recent information on the interactions between circadian rhythms and skin physiology, with a particular focus on skin tissue repair and regeneration. Molecular mechanisms of circadian regulation in skin cells, including the role of core clock genes such as Clock, Bmal1, Per and Cry. These genes control the expression of downstream effectors involved in cell cycle regulation, DNA repair, oxidative stress response and inflammatory pathways. By understanding how these mechanisms operate in healthy and diseased states, we can discover new insights into the temporal dynamics of skin regeneration. In addition, by exploring the therapeutic potential of circadian biology in enhancing skin repair and regeneration, strategies such as topical medications that can be applied in a time-limited manner, phototherapy that is synchronized with circadian rhythms, and pharmacological modulation of clock genes are expected to optimize clinical outcomes. Interventions based on the skin’s natural rhythms can provide a personalized and efficient approach to promote skin regeneration and recovery. This review not only introduces the important role of circadian rhythms in skin biology, but also provides a new idea for future innovative therapies and regenerative medicine based on circadian rhythms.

Objective To explore the role of miR-1260b targeting activating transcription factor 6β(ATF6β)in osteogenic differentia-tion of human periodontal ligament stem cells(hPDLSCs).Methods The periodontal ligament tissue was scraped from the third molar extracted from the patient with periodontitis,and hPDLSCs were isolated and cultured.The proportions of positive cells of CD34,CD45,CD29,CD90 and CD105 were detected by flow cytometry,and the expression of vimentin and pan-cytokeratin were detected by immunofluo-rescence staining.The cellular luciferase activities of ATF6β-WT and ATF6β-MUT in the miR-1260b mimic+WT/MUT group(transfected with miR-1260b mimic and ATF6β-WT/MUT)and the mimic-NC group(transfected with miR-NC and ATF6β-WT/MUT)were analyzed by the dual luciferase reporter gene assay.In addition,the cells were divided into the miR-1260b mimic group(transfected with miR-1260b mimic alone),the ATF6β-OE group(transfected with the ATF6β overexpression vector alone),the combined group(transfected with miR-1260b mimic and ATF6β overexpression vector simultaneously),and the NC group(transfected with empty vector).Alizarin red S staining and alkaline phosphatase staining were performed on hPDLSCs in the NC group,the miR-1260b mimic group,the ATF6β-OE group and the combined group.Meanwhile,the mRNA expression levels of miR-1260b,ATF6β,Runt-related transcription factor 2(Runx2),osteocalcin(OCN),and osteopontin(OPN)in each group of cells were detected by qRT-PCR.The protein expressions of glucose-regulated protein 78(GRP78),C/EBP homologous protein(CHOP),and protein kinase R-like endoplasmic reticulum kinase(PERK)in each group of cells were detected by Western blot.Results The flow cytometry detection showed that CD29,CD90 and CD105 on the surface of the isolated and cultured cells were positive,while CD34 and CD45 were negative.Immunofluorescence staining showed that vimentin in the cells was positive and pan-cytokeratin was negative,which was in line with the characteristics of hPDLSCs.Luciferase assay showed that miR-1260b mimic could significantly reduce the luciferase activity of ATF6β-WT(P<0.05),but had no significant effect on the luciferase activity of ATF6β-MUT(P>0.05).After alizarin red S staining,the staining of hPDLSCs gradually deepened after 3 days,5 days and 7 days of culture,suggesting an enhanced osteogenic differentiation ability.With the enhancement of osteogenic differentiation ability of hPDLSCs,the expression of miR-1260b in the cells showed a gradually increasing trend,while the mRNA and protein expression levels of ATF6β showed a gradually decreasing trend(P<0.05).The results of alizarin red S staining and alkaline phosphatase staining showed that the proportions of positive area in the miR-1260b mimic group were higher than those in the NC group(P<0.05),while the proportions of positive area in the ATF6β-OE group and the combined group were lower than those in the NC group(P<0.05).The mRNA and protein levels of ATF6β in the miR-1260b mimic group were lower than those in the NC group(P<0.05),while the mRNA and protein levels of ATF6β in the ATF6β-OE group and the combined group were higher than those in the NC group(P<0.05).The mRNA levels of Runx2,OCN and OPN in the miR-1260b mimic group were significantly higher than those in the NC group(P<0.05).The mRNA levels of Runx2,OCN and OPN in the ATF6β-OE group and the combined group were significantly lower than those in the NC group(P<0.05).The protein expression levels of GRP78,CHOP and PERK in the miR-1260b mimic group were significantly lower than those in the NC group(P<0.05).The protein expression levels of GRP78,CHOP and PERK in the ATF6β-OE group and the combined group were significantly higher than those in the NC group(P<0.05).Conclusion miR-1260b can inhibit endoplasmic reticulum stress level and promote osteogenic differentiation of hPDLSCs by targeting ATF6β.

Objective This study aimed to investigate the efficacy of modified endoscopic autologous cartilage eustachian tube pharyngeal orifice tuboplasty(MEACETT)in patients with patulous eustachian tube(PET).Meth-ods A retrospective analysis was conducted on the clinical data of 27 patients(30 ears)diagnosed with PET who underwent MEACETT.Autologous cartilage was used through the incision at the posterior end of the inferior turbi-nate and filled into the lateral wall of the pharyngeal orifice of the eustachian tube.Without affecting the movement function of the eustachian tube during swallowing,the collapse of the pharyngeal orifice was fully filled.Before and after the surgery,the visual analogue scale(VAS),the eustachian tube dysfunction questionnaire-7(ETDQ-7)and hospital anxiety and depression scale(HADS)was used for assessment to evaluate the surgical efficacy.Results There was no significant difference in depression scores before and after surgery(P＞0.05).However,postopera-tive anxiety scores,ETDQ-7 scores,and VAS scores were significantly lower than preoperative scores(P＜0.05).Among the 27 patients,9 showed significant symptom relief,13 exhibited partial relief,and 5 had no significant change compared to preoperative symptoms.The overall response rate of the treatment(significant relief and partial relief)was 81.48％(22/27).All surgeries were successfully performed.Except for secretory otitis media occurring in 2 cases,no major complications were observed.Conclusion MEACETT demonstrates significant symptom relief in PET patients,with high surgical safety and low complication rates,making it worthy of clinical promotion.

Objective To evaluate the diagnostic efficacy of the R value in tubomanometry(TMM)for the di-agnosis of patulous eustachian tube(PET).Methods The clinical data of 58 patients with PET and 65 controls were retrospectively analyzed.TMM was performed on both groups under nasopharyngeal pressures of 30,40,and 50 mbar respectively.The diagnostic efficacy of the R value for PET was evaluated through receiver operating char-acteristic(ROC)curves.Results In the control group,the average R values under nasopharyngeal pressures of 30,40,and 50 mbar were 0.86±0.50,0.76±0.41,and 0.68±0.34 respectively.In contrast,the corresponding R values in the PET group were significantly lower,which were 0.56±0.38,0.50±0.36,and 0.46±0.38 respec-tively.According to the ROC curve analysis,the areas under the curve(AUC)at these pressures were 0.62,0.74,and 0.74 respectively.The specificity and sensitivity of the R value under nasopharyngeal pressures of 30,40,and 50 mbar were 76.90％and 54.30％,74.60％and 68.10％,86.90％and 54.30％,respectively.Under pressures of 30,40,and 50 mbar,the incidence rates of R＞1 in the control group and the PET group were 29.23％(38/130)and 12.77％(12/94)(x2=8.69,P=0.003),20.00％(26/130)and 6.38％(6/94)(x2=7.20,P=0.007),10.00％(13/130)and 3.19％(3/94)(x2=2.87,P=0.09)respectively.Conclusion Although the low R value in TMM reflects the presence of PET to some extent,it does not provide adequate sensitivity and specificity to serve as an independent diagnostic criterion for PET.

Objective To study the effects of Hedysarum polysaccharides polysaccharide(HPS)on the farnesoid X receptor(FXR)-fibroblast growth factor-19(FGF19)signaling pathway of diabetes rats.Methods Twelve Wistar male rats were randomly selected as the normal group,and the other rats were fed with a single intraperitoneal injection of streptozotocin(50 mg·kg-1 STZ)and a high sugar and high-fat diet to replicate the diabetes rat model.Model rats were randomly divided into model group,positive control group(given 400 mg·kg-1·d-1 suspension of Bifidobacterium quadruplex live bacterial tablets by gavage),experimental-H,-M,-L groups(given 200,100,and 50 mg·kg-1·d-1 doses of HPS suspension by gavage);normal group,and model group were given equal volume of purified water by gavage once a day for 8 consecutive weeks.Glucose(Glu)was detected by a blood glucose meter;and serum total glyceride(TG)and total cholesterol(TC)were detected by enzyme-linked immunosorbent assay reagent kit;the expressions of FXR、fibroblast growth factor receptors 4(FGFR4)relative mRNA expression level and protein were detected by real-time fluorescence quantitative polymerase chain reaction method and Western blot.Results The Glu concentrations in the normal group,model group,positive control group,and experimental-H groups were(7.66±0.61),(29.25±1.64),(23.31±3.02)and(19.31±5.13)mmol·L-1,respectively;the TG content were(957.00±113.73),(1 345.00±246.44),(958.00±96.53)and(964.00±130.22)μmol·L-1,respectively;the TC content were(161.65±4.53),(302.19±5.35),(236.09±5.14)and(165.58±2.58)μmol·L-1,respectively;the expression of FXR relative mRNA expression level were 1.00±0.06,0.48±0.02,0.67±0.04 and 0.92±0.04,respectively;the expression of FGFR4 relative mRNA expression level were 1.00±0.04,0.17±0.01,0.48±0.04 and 0.41±0.03;respectively.The above indexes of the model group were compared with the control group,and the above indexes of the control group and the experimental-H group were compared with the model group,and the differences were statistically significant(all P＜0.01).Conclusion HPS improves blood sugar,lowers blood lipids,and protects liver and intestinal tissues,possibly by regulating the FXR-FGF19 signaling pathway in intestinal tissue,and regulating bile acid synthesis.

Objective To study the effects of Hedysarum polysaccharides polysaccharide(HPS)on the farnesoid X receptor(FXR)-fibroblast growth factor-19(FGF19)signaling pathway of diabetes rats.Methods Twelve Wistar male rats were randomly selected as the normal group,and the other rats were fed with a single intraperitoneal injection of streptozotocin(50 mg·kg-1 STZ)and a high sugar and high-fat diet to replicate the diabetes rat model.Model rats were randomly divided into model group,positive control group(given 400 mg·kg-1·d-1 suspension of Bifidobacterium quadruplex live bacterial tablets by gavage),experimental-H,-M,-L groups(given 200,100,and 50 mg·kg-1·d-1 doses of HPS suspension by gavage);normal group,and model group were given equal volume of purified water by gavage once a day for 8 consecutive weeks.Glucose(Glu)was detected by a blood glucose meter;and serum total glyceride(TG)and total cholesterol(TC)were detected by enzyme-linked immunosorbent assay reagent kit;the expressions of FXR、fibroblast growth factor receptors 4(FGFR4)relative mRNA expression level and protein were detected by real-time fluorescence quantitative polymerase chain reaction method and Western blot.Results The Glu concentrations in the normal group,model group,positive control group,and experimental-H groups were(7.66±0.61),(29.25±1.64),(23.31±3.02)and(19.31±5.13)mmol·L-1,respectively;the TG content were(957.00±113.73),(1 345.00±246.44),(958.00±96.53)and(964.00±130.22)μmol·L-1,respectively;the TC content were(161.65±4.53),(302.19±5.35),(236.09±5.14)and(165.58±2.58)μmol·L-1,respectively;the expression of FXR relative mRNA expression level were 1.00±0.06,0.48±0.02,0.67±0.04 and 0.92±0.04,respectively;the expression of FGFR4 relative mRNA expression level were 1.00±0.04,0.17±0.01,0.48±0.04 and 0.41±0.03;respectively.The above indexes of the model group were compared with the control group,and the above indexes of the control group and the experimental-H group were compared with the model group,and the differences were statistically significant(all P＜0.01).Conclusion HPS improves blood sugar,lowers blood lipids,and protects liver and intestinal tissues,possibly by regulating the FXR-FGF19 signaling pathway in intestinal tissue,and regulating bile acid synthesis.

AIM To investigate the repair effects of tauroursodeoxycholic acid(TUDCA)combined with bone marrow mesenchymal stem cells(BMSCs)transplantation on spinal cord injury(SCI)in rats.METHODS The rats were randomly divided into the sham operation group,the model group,the TUDCA group,the BMSCs transplantation group and the combination therapy of TUDCA and BMSCs transplantation group,with the SCI rat model established by Allen's method.The next day after modeling,the rats of TUDCA and combination therapy groups were given 200 mg/kg TUDCA by gavage.On the 3rd day after modeling,rats in BMSCs transplantation group and combination therapy group were injected with 1 mL tuned bone marrow BMSCs(the 3rd generation,1× 106/mL)via tail vein.Rats in the sham operation group and the model group were given gastric perfusion of normal saline and injection of 1 mL PBS through tail vein.On the 3rd,7th and 14th day after modeling,the rats had their motor function of hind limbs observed and BBB score determined.After the corresponding drug administration,the rats had their movement track of hind limbs recorded by footprint experiment;their the protein expressions of IL-6,IL-10,Arg-1,PI3K and Akt in spinal cord tissue detected by Western blot;their pathological changes of spinal cord tissue observed by HE staining and Nissl staining;and their expressions of MAP2,GAP43 and GFAP detected by immunofluorescence staining.RESULTS Compared with the model group,the groups intervened with TUDCA,or BMSCs transplantation,or combination therapy shared improved hind limb function and spinal cord histomorphology(P＜0.05);increased fluorescence intensity of MAP2 and GAP43,and protein expressions of IL-10,Arg-1,p-PI3K and p-Akt(P＜0.05);decreased fluorescence intensity of GFAP and IL-6 protein expressions(P＜0.05);among which the combination therapy group took the lead(P＜0.05).CONCLUSION The combination therapy of TUDCA and BMSCs transplantation may restore the function of the rat model of SCI by reducing inflammatory reaction,alleviating secondary injury,and promoting axon and myelin regeneration via PI3K/Akt signaling pathway.

This study aims to explore the synergistic effects of the main components in salvianolic acids for Injection(SAFI) on key pathological events in cerebral ischemia, elucidating the pharmacological characteristics of SAFI in neuroprotection. Two major pathological gene modules related to endothelial injury and neuroinflammation in cerebral ischemia were mined from single-cell data. According to the topological distance calculated in network medicine, potential synergistic component combinations of SAFI were screened out. The results showed that the combination of caffeic acid and salvianolic acid B scored the highest in addressing both endothelial injury and neuroinflammation, demonstrating potential synergistic effects. The cell experiments confirmed that the combination of these two components at a ratio of 1∶1 significantly protected brain microvascular endothelial cells(bEnd.3) from oxygen-glucose deprivation/reoxygenation(OGD/R)-induced reperfusion injury and effectively suppressed lipopolysaccharide(LPS)-induced neuroinflammatory responses in microglial cells(BV-2). This study provides a new method for uncovering synergistic effects among active components in traditional Chinese medicine(TCM) and offers novel insights into the multi-component, multi-target acting mechanisms of TCM.
Brain Ischemia/metabolism* ; Neuroprotective Agents/pharmacology* ; Animals ; Drugs, Chinese Herbal/administration & dosage* ; Benzofurans/pharmacology* ; Mice ; Drug Synergism ; Caffeic Acids/pharmacology* ; Polyphenols/pharmacology* ; Humans ; Alkenes/pharmacology* ; Endothelial Cells/drug effects* ; Depsides