“Runner’s high” refers to a momentary sense of pleasure that suddenly appears during running or other exercise activities, characterized by anti-anxiety, pain relief, and other symptoms. The neurobiological mechanism of “runner’s high” is unclear. This review summarizes human and animal models for studying “runner’s high”, analyzes the neurotransmitters and neural circuits involved in runner’s high, and elucidates the evidence and shortcomings of researches related to “runner’s high”. This review also provides prospects for future research. Research has found that exercise lasting more than 30 min and with an intensity exceeding 70% of the maximum heart rate can reach a “runner’s high”. Human experiments on “runner’s high” mostly use treadmill exercise intervention, and evaluate it through questionnaire surveys, measurement of plasma AEA, miRNA and other indicators. Animal experiments often use voluntary wheel running intervention, and evaluate it through behavioral experiments such as conditional place preference, light dark box experiments (anxiety), hot plate experiments (pain sensitivity), and measurement of plasma AEA and other indicators. Dopamine, endogenous opioid peptides, endogenous cannabinoids, brain-derived neurotrophic factor, and other substances increase after exercise, which may be related to the “runner’s high”. However, attention should be paid to the functional differences of these substances in the central and peripheral regions, as well as in different brain regions. Moreover, current studies have not identified the targets of the neurotransmitters or neural factors mentioned above, and further in-depth researches are needed. The mesolimbic dopamine system, prefrontal cortex-nucleus accumbens projection, ventral hippocampus-nucleus accumbens projection, red nucleus-ventral tegmental area projection, cerebellar-ventral tegmental area projection, and brain-gut axis may be involved in the regulation of runner’s high, but there is a lack of direct evidence to prove their involvement. There are still many issues that need to be addressed in the research on the neurobiological mechanisms of “runner’s high”. (1) Most studies on “runner’s high” involve one-time exercise, and the characteristics of changes in “runner’s high” during long-term exercise still need to be explored. (2) The using of scales to evaluate subjects lead to the lacking of objective indicators. However, some potential biomarkers (such as endocannabinoids) have inconsistent characteristics of changes after one-time and long-term exercise. (3) The neurotransmitters involved in the formation of the “runner’s high” all increase in the peripheral and/or central nervous system after exercise. Attention should be paid to whether peripheral substances can enter the blood-brain barrier and the binding effects of neurotransmitters to different receptors are completely different in different brain regions. (4) Most of the current evidence show that some brain regions are activated after exercise. Is there a functional circuit mediating “runner’s high” between these brain regions? (5) Although training at a specific exercise intensity can lead to “runner’s high”, most runners have not experienced “runner’s high”. Can more scientific training methods or technological means be used to make it easier for people to experience the “runner’s high” and thus be more willing to engage in exercise? (6) The “runner’s high” and “addiction” behaviors are extremely similar, and there are evidences that exercise can reverse addictive behaviors. However, why is there still a considerable number of people in the sports population and even athletes who smoke or use addictive drugs instead of pursuing the “pleasure” brought by exercise? Solving the problems above is of great significance for enhancing the desire of exercise, improving the clinical application of neurological and psychiatric diseases through exercise, and enhancing the overall physical fitness of the population.

Aim To explore the effects of D-limonene on the steatosis of primary mouse hepatocytes and its potential mechanism of action.Methods Oleic acid-induced steatosis in primary mouse hepatocytes was used as a model to observe the effects of D-limonene on cell viability,cellular lipid content,and intracellular expression of proteins such as AMP-activated protein kinase(AMPK),acetyl-coenzyme A carboxylase 1(ACC1),and carnitine palmitoyl transferase 1A(CPT1A).Results It was found that a low dose of D-limonene could effectively enhance the viability of primary mouse hepatocytes.When oleic acid at a con-centration of 300 μmol·L-1 successfully induced steatosis in primary mouse hepatocytes,D-limonene re-duced the lipid content of the cells,and D-limonene up-regulated the cellular AMPK expression level,down-regulated the cellular ACC1 and fatty acid synthetase(FAS)expression levels,which in turn promoted the overexpression of CPT1A.Conclusions D-limonene has the effect of reducing lipid deposition in primary mouse hepatocytes,and the mechanisms may be related to the activation of AMPK,the inhibitions of ACC1 and FAS,and the up-regulation of CPT1A protein expres-sion level.

Objective To analyze the risk factors associated with early recurrence after surgery for concomitant exo-tropia and establish a Nomogram prediction model.Methods A retrospective analysis was conducted on 243 cases(486 eyes)of concomitant exotropia treated in the Ophthalmology Department of our hospital from October 2015 to October 2021.The patients were divided into a training set(n=170)and a validation set(n=73)at a ratio of 7∶3.The Lasso re-gression,Boruta algorithm,and random forest algorithm were used to screen risk variables related to postoperative recur-rence of concomitant exotropia.The Spearman correlation analysis and variance inflation factor(VIF)were used to assess collinearity among variables,and a Nomogram prediction model was established using multivariate Cox regression.The re-ceiver operating characteristic curve,calibration curve,and clinical decision curve of the model at 6 months,18 months,and 24 months after surgery were used to assess the efficacy of the model.Results Three machine learning methods in-cluding Lasso regression,Boruta algorithm,and random forest algorithm identified six significant variables that might con-tribute to early recurrence after strabismus surgery from 22 risk variables in both training and validation sets.No collineari-ty was found among the six variables(r＜0.6,VIF＜5).Multivariate Cox regression revealed that strabismus type(inter-mittent exotropia),preoperative strabismus angle,best-corrected visual acuity(BCVA)in the right eye,BCVA in both eyes,and surgical procedures(unilateral lateral rectus recession)were risk factors for early recurrence after surgery for concomitant exotropia.Meanwhile,a Nomogram prediction model was constructed based on these 6 factors.The receiver operating characteristic,calibration,and clinical decision curves indicated that the prediction model had good accuracy,consistency,and clinical applicability.Conclusion Nomogram prediction model can effectively predict the risk of early recurrence after surgery for concomitant exotropia,and provides a reference for ophthalmologists to intervene early in pa-tients.

Objective To analyze the changing trend of the disease burden of age-related macular degeneration(AMD)in China from 1990 to 2021 and the impact of age,period,and cohort effects,and to predict the standardized prev-alence and disability-adjusted life year(DALY)rate of AMD in China from 2022 to 2035.Methods The data on the preva-lence of AMD,the number of AMD patients,DALYs,and DALY rates in China from 1990 to 2021 were obtained from the Global Burden of Disease(GBD 2021).The segmented regression model was used to analyze the trend changes in the prev-alence and DALY of patients with AMD in China,the age-period-cohort(APC)model was employed to estimate the age,period,and cohort effects related to the prevalence risk and DALY risk of AMD,and the Bayesian age-period cohort model was used to analyze the standardized prevalence and DALY rate of AMD in China from 2022 to 2035.Results Compared with 1990,the number of AMD patients and the prevalence of this disease in China in 2021 increased by 199.94％and 148.02％,respectively,and the DALYs and DALY rate increased by 183.95％and 134.80％,respectively,with the higher value of relevant indicators observed in females compared with males.From 1990 to 2021,the standardized prevalence of AMD in China showed an increasing trend,with the average annual percentage change(AAPC)being 0.17％.In contrast,the standardized DALY rate of AMD showed a decreasing trend,with the AAPC being-0.03％.The results of the age-peri-od-cohort model showed that the longitudinal age curves for both the prevalence and DALY rate of AMD in China showed an increasing and then decreasing trend,peaking at 85-89 years of age.Over time,the prevalence risk of AMD increased and then decreased,while the DALY risk continued to decline.The birth cohort analysis results showed that the overall fluctua-tion of the AMD prevalence risk cohort effect in China was small,with a decline first and then a fluctuating increase.Mean-while,the DALY risk gradually decreased as the birth cohort moved backward.It can be predicted that both the standard-ized prevalence and the standardized DALY rate of AMD may present an upward trend in China from 2022 to 2035.Conclu-sion From 1990 to 2021,the standardized prevalence of AMD in China displays an upward trend,while its standardized DALY rate exhibits a downward trend.Notably,the disease burden is more pronounced in the female population compared with the male population.With the continued aging of the population,it can be predicted that both the standardized preva-lence and DALY rate of AMD will escalate from 2022 to 2035.This finding underscores the need for targeted interventions,particularly for elderly women.Meanwhile,it is necessary to enhance health education for the whole population and formu-late effective public health policies to alleviate the disease burden associated with AMD in China.

Objective To analyze the changing trend of the disease burden of age-related macular degeneration(AMD)in China from 1990 to 2021 and the impact of age,period,and cohort effects,and to predict the standardized prev-alence and disability-adjusted life year(DALY)rate of AMD in China from 2022 to 2035.Methods The data on the preva-lence of AMD,the number of AMD patients,DALYs,and DALY rates in China from 1990 to 2021 were obtained from the Global Burden of Disease(GBD 2021).The segmented regression model was used to analyze the trend changes in the prev-alence and DALY of patients with AMD in China,the age-period-cohort(APC)model was employed to estimate the age,period,and cohort effects related to the prevalence risk and DALY risk of AMD,and the Bayesian age-period cohort model was used to analyze the standardized prevalence and DALY rate of AMD in China from 2022 to 2035.Results Compared with 1990,the number of AMD patients and the prevalence of this disease in China in 2021 increased by 199.94％and 148.02％,respectively,and the DALYs and DALY rate increased by 183.95％and 134.80％,respectively,with the higher value of relevant indicators observed in females compared with males.From 1990 to 2021,the standardized prevalence of AMD in China showed an increasing trend,with the average annual percentage change(AAPC)being 0.17％.In contrast,the standardized DALY rate of AMD showed a decreasing trend,with the AAPC being-0.03％.The results of the age-peri-od-cohort model showed that the longitudinal age curves for both the prevalence and DALY rate of AMD in China showed an increasing and then decreasing trend,peaking at 85-89 years of age.Over time,the prevalence risk of AMD increased and then decreased,while the DALY risk continued to decline.The birth cohort analysis results showed that the overall fluctua-tion of the AMD prevalence risk cohort effect in China was small,with a decline first and then a fluctuating increase.Mean-while,the DALY risk gradually decreased as the birth cohort moved backward.It can be predicted that both the standard-ized prevalence and the standardized DALY rate of AMD may present an upward trend in China from 2022 to 2035.Conclu-sion From 1990 to 2021,the standardized prevalence of AMD in China displays an upward trend,while its standardized DALY rate exhibits a downward trend.Notably,the disease burden is more pronounced in the female population compared with the male population.With the continued aging of the population,it can be predicted that both the standardized preva-lence and DALY rate of AMD will escalate from 2022 to 2035.This finding underscores the need for targeted interventions,particularly for elderly women.Meanwhile,it is necessary to enhance health education for the whole population and formu-late effective public health policies to alleviate the disease burden associated with AMD in China.

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

This study aimed to characterize and identify the non-volatile components in aqueous and ethanolic extracts of the stems and leaves of Rhododendron tomentosum by using sensitive and efficient ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry(UHPLC-Q-TOF-MS) combined with a self-built information database. By comparing with reference compounds, analyzing fragment ion information, searching relevant literature, and using a self-built information database, 118 compounds were identified from the aqueous and ethanolic extracts of R. tomentosum, including 35 flavonoid glycosides, 15 phenolic glycosides, 12 flavonoids, 7 phenolic acids, 7 phenylethanol glycosides, 6 tannins, 6 phospholipids, 5 coumarins, 5 monoterpene glycosides, 6 triterpenes, 3 fatty acids, and 11 other types of compounds. Among them, 102 compounds were reported in R. tomentosum for the first time, and 36 compounds were identified by comparing them with reference compounds. The chemical components in the ethanolic and aqueous extracts of R. tomentosum leaves and stems showed slight differences, with 84 common chemical components accounting for 71.2% of the total 118 compounds. This study systematically characterized and identified the non-volatile chemical components in the ethanolic and aqueous extracts of R. tomentosum for the first time. The findings provide a reference for active ingredient research, quality control, and product development of R. tomentosum.
Rhododendron/chemistry* ; Chromatography, High Pressure Liquid/methods* ; Drugs, Chinese Herbal/chemistry* ; Mass Spectrometry/methods* ; Plant Leaves/chemistry*

Emodin is a hydroxyanthraquinone compound that is widely distributed and has multiple pharmacological activities, including anti-diarrheal, anti-inflammatory, and liver-protective effects. Research indicates that emodin may be one of the main components responsible for inducing hepatotoxicity. However, studies on the mechanisms of liver injury are relatively limited, particularly those related to bile acids(BAs) metabolism. This study aims to systematically investigate the effects of different dosages of emodin on BAs metabolism, providing a basis for the safe clinical use of traditional Chinese medicine(TCM)containing emodin. First, this study evaluated the safety of repeated administration of different dosages of emodin over a 5-week period, with a particular focus on its impact on the liver. Next, the composition and content of BAs in serum and liver were analyzed. Subsequently, qRT-PCR was used to detect the mRNA expression of nuclear receptors and transporters related to BAs metabolism. The results showed that 1 g·kg~(-1) emodin induced hepatic damage, with bile duct hyperplasia as the primary pathological manifestation. It significantly increased the levels of various BAs in the serum and primary BAs(including taurine-conjugated and free BAs) in the liver. Additionally, it downregulated the mRNA expression of farnesoid X receptor(FXR), retinoid X receptor(RXR), and sodium taurocholate cotransporting polypeptide(NTCP), and upregulated the mRNA expression of cholesterol 7α-hydroxylase(CYP7A1) in the liver. Although 0.01 g·kg~(-1) and 0.03 g·kg~(-1) emodin did not induce obvious liver injury, they significantly increased the level of taurine-conjugated BAs in the liver, suggesting a potential interference with BAs homeostasis. In conclusion, 1 g·kg~(-1) emodin may promote the production of primary BAs in the liver by affecting the FXR-RXR-CYP7A1 pathway, inhibit NTCP expression, and reduce BA reabsorption in the liver, resulting in BA accumulation in the peripheral blood. This disruption of BA homeostasis leads to liver injury. Even doses of emodin close to the clinical dose can also have a certain effect on the homeostasis of BAs. Therefore, when using traditional Chinese medicine or formulas containing emodin in clinical practice, it is necessary to regularly monitor liver function indicators and closely monitor the risk of drug-induced liver injury.
Emodin/administration & dosage* ; Bile Acids and Salts/metabolism* ; Animals ; Male ; Liver/injuries* ; Chemical and Drug Induced Liver Injury/genetics* ; Drugs, Chinese Herbal/adverse effects* ; Humans ; Rats, Sprague-Dawley ; Mice ; Rats

In this study, lipopolysaccharide(LPS), ovalbumin(OVA), and compound 48/80(C48/80) were administered to establish non-infectious pneumonia models under simulated clinical conditions, and the correlation between their pathological characteristics and traditional Chinese medicine(TCM) syndromes was compared, providing the basis for the selection of appropriate animal models for TCM efficacy evaluation. An acute pneumonia model was established by nasal instillation of LPS combined with intraperitoneal injection for intensive stimulation. Three doses of OVA mixed with aluminum hydroxide adjuvant were injected intraperitoneally on days one, three, and five and OVA was administered via endotracheal drip for excitation on days 14-18 to establish an OVA-induced allergic pneumonia model. A single intravenous injection of three doses of C48/80 was adopted to establish a C48/80-induced pneumonia model. By detecting the changes in peripheral blood leukocyte classification, lung tissue and plasma cytokines, immunoglobulins(Ig), histamine levels, and arachidonic acid metabolites, the multi-dimensional analysis was carried out based on pathological evaluation. The results showed that the three models could cause pulmonary edema, increased wet weight in the lung, and obvious exudative inflammation in lung tissue pathology, especially for LPS. A number of pyrogenic cytokines, inclading interleukin(IL)-6, interferon(IFN)-γ, IL-1β, and IL-4 were significantly elevated in the LPS pneumonia model. Significantly increased levels of prostacyclin analogs such as prostaglandin E2(PGE2) and PGD2, which cause increased vascular permeability, and neutrophils in peripheral blood were significantly elevated. The model could partly reflect the clinical characteristics of phlegm heat accumulating in the lung or dampness toxin obstructing the lung. The OVA model showed that the sensitization mediators IgE and leukotriene E4(LTE4) were increased, and the anti-inflammatory prostacyclin 6-keto-PGF2α was decreased. Immune cells(lymphocytes and monocytes) were decreased, and inflammatory cells(neutrophils and basophils) were increased, reflecting the characteristics of "deficiency", "phlegm", or "dampness". Lymphocytes, monocytes, and basophils were significantly increased in the C48/80 model. The phenotype of the model was that the content of histamine, a large number of prostacyclins(6-keto-PGE1, PGF2α, 15-keto-PGF2α, 6-keto-PGF1α, 13,14-D-15-keto-PGE2, PGD2, PGE2, and PGH2), LTE4, and 5-hydroxyeicosatetraenoic acid(5S-HETE) was significantly increased, and these indicators were associated with vascular expansion and increased vascular permeability. The pyrogenic inflammatory cytokines were not increased. The C48/80 model reflected the characteristics of cold and damp accumulation. In the study, three non-infectious pneumonia models were constructed. The LPS model exhibited neutrophil infiltration and elevated inflammatory factors, which was suitable for the efficacy study of TCM for clearing heat, detoxifying, removing dampness, and eliminating phlegm. The OVA model, which took allergic inflammation as an index, was suitable for the efficacy study of Yiqi Gubiao formulas. The C48/80 model exhibited increased vasoactive substances(histamine, PGs, and LTE4), which was suitable for the efficacy study and evaluation of TCM for warming the lung, dispersing cold, drying dampness, and resolving phlegm. The study provides a theoretical basis for model selection for the efficacy evaluation of TCM in the treatment of pneumonia.
Animals ; Disease Models, Animal ; Mice ; Pneumonia/genetics* ; Medicine, Chinese Traditional ; Male ; Humans ; Cytokines/immunology* ; Female ; Lipopolysaccharides/adverse effects* ; Lung/drug effects* ; Drugs, Chinese Herbal ; Ovalbumin ; Mice, Inbred BALB C

ObjectiveTo explore the mechanism by which Zuoguiwan improves the pancreas development in the gestational diabetes mellitus （GDM） model by observing the effects of Zuoguiwan on the expression of key regulatory factors in different stages of pancreas development. MethodsPregnant Wistar rats were randomly assigned into blank， model， insulin detemir （20 U·kg^-1） and Zuoguiwan （1.89 g·kg^-1） groups （n=18）. GDM was induced by peritoneal injection of streptozotocin on day 6.5 （E6.5d） in the embryonic stage， and the blank group was given an equal volume of sodium citrate buffer. The modeling performance was assessed by measuring the blood glucose of pregnant rats. Except the blank group and model group， pregnant rats in other groups were administrated with corresponding drugs from E9.5d to delivery. The random blood glucose of pregnant rats was monitored， and the embryos and offspring rats were measured for the length and weighed on E12.5d， E18.5d and day 21 after birth （B21d）. The Lee's index of rats on B21d was calculated. Enzyme-linked immunosorbent assay （ELISA） was employed to measure the fasting insulin （FINS） levels of B22d rats and the Homeostasis Model Assessment for Insulin Resistance （HOMA-IR） was calculated. The serum levels of aspartate aminotransferase （AST）， alanine aminotransferase （ALT）， total bilirubin （TBIL）， total cholesterol （CHO）， triglyceride （TG）， high-density lipoprotein cholesterol （HDL）， and low-density lipoprotein cholesterol （LDL） in E18.5d pregnant rats and B22d offspring were determined. The pathological changes in the pancreas of E12.5d， E18.5d and B22d rats were observed by hematoxylin-eosin （HE） staining. Western blot was used to determine the protein levels of pancreatic duodenal homeobox 1 （Pdx1）， pancreas-specific transcription factor 1a （Ptf1a）， and sex-determining region Y-box protein 9 （Sox9） in the pancreas of E12.5d embryos， Pdx1， Nkx2 homeobox 2 （Nkx2.2）， and hairy and enhancer of split-1 （Hes1） in the pancreas of E18.5d embryos， and Pdx1， v-maf musculoaponeurotic fibrosarcoma oncogene homolog A （Mafa）， and NK transcription factor-related homeobox gene family 6 locus 1 （Nkx6.1） in the pancreas of B22d rats. ResultsCompared with the blank group， the model group showed elevated blood glucose levels in pregnant rats on B0d， E9.5d， E12.5d， E15.5d， and E18.5d （P<0.05， P<0.01）， decreased body weight and body length （P<0.01） and increased Lee's index in the offspring. In addition， the B22d offspring showed rising levels of FBG， FINS， HOMA-IR， AST， and TG （P<0.01）， a declined level of HDL （P<0.01）， and pancreatic acinous cells with edema and loose arrangement. The pregnant rats on E18.5d exhibited raised levels of ALT， AST， and TG （P<0.05， P<0.01） in the pancreas and a declined level of HDL （P<0.05）. The E12.5d embryos showed up-regulated protein levels of Pdx1， Sox9， and Ptf1a in the pancreas （P<0.01） and the E18.5d embryos exhibited down-regulated protein levels of Pdx1， Nkx2.2， and Hes1 in the pancreas （P<0.01）. The protein levels of Pdx1， Nkx6.1， and Mafa in the pancreas of B22d offspring were down-regulated （P<0.01）. Compared with the model group， the insulin group exhibited lowered blood glucose in pregnant rats on B0d， E15.5d， and E18.5d （P<0.05， P<0.01）. The offspring in all treatment groups showcased increased body weight and body length （P<0.01） and decreased Lee's index. The B22d offspring exhibited declined levels of FBG， FINS， and HOMA-IR in the insulin group （P<0.01） and lowered levels of FBG and HOMA-IR in the Zuoguiwan group （P<0.01）. The B22d offspring in all the treatment groups showed reduced levels of ALT， AST， TBIL， CHO， TG， and LDL， a raised level of HDL， and alleviated edema of pancreatic acinous cells. The pregnant rats on E18.5d demonstrated declined levels of TG and ALT （P<0.05， P<0.01） and an elevated level of HDL （P<0.05）. The pancreas of E12.5d embryos presented down-regulated protein levels of Pdx1 and Sox9 and an up-regulated protein level of Ptf1a in the insulin group （P<0.05）. The pancreas of E12.5d embryos in the Zuoguiwan group presented down-regulated protein levels of Pdx1， Sox9， and Ptf1a （P<0.01）. All the treatment groups showed up-regulated protein levels of Pdx1， Nkx2.2， and Hes1 in the pancreas of E18.5d embryos （P<0.01） and Pdx1， Nkx6.1， and Mafa in the pancreas of B22d embryos （P<0.05， P<0.01）. ConclusionZuoguiwan can promote the growth and development and ameliorate the pathological changes in the pancreas of the offspring of GDM model by regulating the expression of Pdx1 pathway-related regulatory factors in different stages of pancreas development.