Lactate, with a chemical formula of C₃H₆O₃, is an intermediate product of glucose metabolism in the body and a raw material for hepatic gluconeogenesis. Under physiological resting conditions, the body mainly relies on aerobic oxidation of sugar and fat for energy supply, so the blood lactate concentration is lower. However, during exercise, the enhanced glycolysis in skeletal muscles leads to the significant release of lactate into the bloodstream, causing a marked increase in blood lactate concentration. Traditionally, lactate has been regarded as a metabolic waste product of glycolysis and a contributor to exercise-induced fatigue. Nevertheless, recent studies have revealed that, in humans, lactate is a major vehicle for carbohydrate carbon distribution and metabolism, serving not only as an energy substance alongside glucose but also as a vital component in various biological pathways involved in cardiac energetics, muscle adaptation, brain function, growth and development, and inflammation therapy. Two primary pathways can elevate lactate levels in neurons during exercise. One is peripheral skeletal muscle-derived lactate, which can enter the bloodstream and cross the blood-brain barrier into the brain with the assistance of monocarboxylate transporters (MCTs) from the solute carrier family 16 (SLC16). The other is the central brain-derived pathway. During exercise, neuronal activity is enhanced, promoting the secretion of neuroactive substances such as glutamate, norepinephrine, and serotonin in the brain. This activates astrocytes to break down glycogen into lactate and stimulates glutamate from the presynaptic terminal into the synaptic cleft. It upregulates the glucose transport protein-1 (GLUT-1) expression, allowing astrocytes to convert glucose into lactate through glycolysis. The lactate is produced via peripheral pathways and central pathways during exercise are transported by astrocyte membrane monocarboxylate transporters MCT1 and MCT4 to the extracellular space, where neurons take it up through neuronal cell membrane MCT2. The lactate in neurons can serve as an alternative energy source of glucose for neuronal functional activities, meeting the increased energy demands of synaptic activity during exercise, and maintaining energy balance and normal physiological function in the brain. Additionally, acting as a signaling molecule lactate can enhance synaptic plasticity through the SIRT1/PGC-1α/FNDC5 and ERK1/2 signaling pathways, lactate can promote angiogenesis by upregulating VEGF-A expression through the PI3K/Akt and ERK1/2 signaling pathways, stimulate neurogenesis via the Akt/PKB signaling pathway, and reduce neuroinflammation through activation of the “lactate timer”. Overall, lactate contributes to the protection of neurons, the promotion of learning and memory, the enhancement of synaptic plasticity, and the reduction of neuroinflammation in the nervous system. While lactate may serve as a potential mediator for information exchange between the peripheral and central nervous systems during exercise, further experimental research is needed to elucidate its action mechanisms in the nervous system. In addition, future studies should utilize advanced neurophysiological and molecular biology techniques to uncover the importance of lactate in maintaining brain function and preventing neurological diseases. Accordingly, this article first reviews the historical research on lactate, then summarizes the metabolic characteristics and neuronal sources of lactate, and finally explores the role and mechanisms of exercise-induced lactate in the nervous system, aiming to provide new perspectives and targets for understanding the mechanisms underlying exercise promotion of brain health.

This study aims to explore the effects of Buzhong Yiqi Decoction(BYD) on the cyclic guanosine monophosphate-adenosine monophosphate synthase(cGAS)-stimulator of interferon genes(STING) signaling pathway in the mouse model of autoimmune thyroiditis(AIT) and the mechanism of BYD in alleviating the immune injury. Forty-eight NOD.H-2~(h4) mice were assigned into normal, model, low-, medium-, and high-dose BYD, and selenium yeast tablets groups(n=8). Mice of 8 weeks old were treated with 0.05% sodium iodide solution for 8 weeks for the modeling of AIT and then administrated with corresponding drugs by gavage for 8 weeks before sampling. High performance liquid chromatography was employed to measure the astragaloside Ⅳ content in BYD. Hematoxylin-eosin staining was employed to observe the pathological changes in the mouse thyroid tissue. Enzyme-linked immunosorbent assay was employed to measure the serum levels of thyroid peroxidase antibody(TPO-Ab), thyroglobulin antibody(TgAb), and interferon-γ(IFN-γ). Flow cytometry was employed to detect the distribution of T cell subsets in the spleen. The immunohistochemical method was used to detect the expression of cGAS, STING, TANK-binding kinase 1(TBK1), and interferon regulatory factor 3(IRF3). Real-time PCR and Western blot were employed to determine the mRNA and protein levels, respectively, of markers related to the cGAS-STING signaling pathway in the thyroid tissue. The results showed that the content of astragaloside Ⅳ in BYD was(7.06±0.08) mg·mL~(-1). Compared with the normal group, the model group showed disrupted structures of thyroid follicular epithelial cells, massive infiltration of lymphocytes, and elevated levels of TgAb and TPO-Ab. Compared with the model group, the four treatment groups showed intact epithelial cells, reduced lymphocyte infiltration, and lowered levels of TgAb and TPO-Ab. Compared with the normal group, the model group showed increases in the proportions of Th1 and Th17 cells, a decrease in the proportion of Th2 cells, and an increase in the IFN-γ level. Compared with the model group, the four treatment groups presented decreased proportions of Th1 and Th17 cells and lowered levels of IFN-γ, and the medium-dose BYD group showed an increase in the proportion of Th2 cells. Compared with the normal group, the modeling up-regulated the mRNA levels of cGAS, STING, TBK1, and IRF3 and the protein levels of cGAS, p-STING, p-TBK1, and p-IRF3. Compared with the model group, the four treatment groups showed reduced levels of cGAS, STING, TBK1, and IRF3-positive products, down-regulated mRNA levels of cGAS, STING, and TBK1, and down-regulated protein levels of cGAS and p-STING. The high-dose BYD group showed down-regulations in the mRNA level of IRF3 and the protein levels of p-TBK1 and p-IRF3. The above results indicate that BYD can repair the imbalance of T cell subsets, alleviate immune injury, and reduce thyroid lymphocyte infiltration in AIT mice by inhibiting the cGAS-STING signaling pathway.
Animals ; Drugs, Chinese Herbal/administration & dosage* ; Signal Transduction/drug effects* ; Thyroiditis, Autoimmune/metabolism* ; Mice ; Membrane Proteins/metabolism* ; Mice, Inbred NOD ; Humans ; Female ; Nucleotidyltransferases/metabolism* ; Male ; Disease Models, Animal

[This corrects the article DOI: 10.1016/j.apsb.2022.05.019.].

OBJECTIVE: This study aimed to explore the association between body mass index (BMI) and mortality based on the 10-year population-based multicenter prospective study. METHODS: A general population-based multicenter prospective study was conducted at four sites in rural China between 2013 and 2023. Multivariate Cox proportional hazards models and restricted cubic spline analyses were used to assess the association between BMI and mortality. Stratified analyses were performed based on the individual characteristics of the participants. RESULTS: Overall, 19,107 participants with a sum of 163,095 person-years were included and 1,910 participants died. The underweight (< 18.5 kg/m ²) presented an increase in all-cause mortality (adjusted hazards ratio [ aHR] = 2.00, 95% confidence interval [ CI]: 1.66-2.41), while overweight (≥ 24.0 to < 28.0 kg/m ²) and obesity (≥ 28.0 kg/m ²) presented a decrease with an aHR of 0.61 (95% CI: 0.52-0.73) and 0.51 (95% CI: 0.37-0.70), respectively. Overweight ( aHR = 0.76, 95% CI: 0.67-0.86) and mild obesity ( aHR = 0.72, 95% CI: 0.59-0.87) had a positive impact on mortality in people older than 60 years. All-cause mortality decreased rapidly until reaching a BMI of 25.7 kg/m ² ( aHR = 0.95, 95% CI: 0.92-0.98) and increased slightly above that value, indicating a U-shaped association. The beneficial impact of being overweight on mortality was robust in most subgroups and sensitivity analyses. CONCLUSION This study provides additional evidence that overweight and mild obesity may be inversely related to the risk of death in individuals older than 60 years. Therefore, it is essential to consider age differences when formulating health and weight management strategies.
Humans ; Body Mass Index ; China/epidemiology* ; Male ; Female ; Middle Aged ; Prospective Studies ; Rural Population/statistics & numerical data* ; Aged ; Follow-Up Studies ; Adult ; Mortality ; Cause of Death ; Obesity/mortality* ; Overweight/mortality*

Objective This study aimed to evaluate whether the onset of the plateau phase of slow hepatitis B surface antigen decline in patients with chronic hepatitis B treated with intermittent interferon therapy is related to the frequency of dendritic cell subsets and expression of the costimulatory molecules CD40,CD80,CD83,and CD86. Method This was a cross-sectional study in which patients were divided into a natural history group(namely NH group),a long-term oral nucleoside analogs treatment group(namely NA group),and a plateau-arriving group(namely P group).The percentage of plasmacytoid dendritic cell and myeloid dendritic cell subsets in peripheral blood lymphocytes and monocytes and the mean fluorescence intensity of their surface costimulatory molecules were detected using a flow cytometer. Results In total,143 patients were enrolled(NH group,n = 49;NA group,n = 47;P group,n = 47).The results demonstrated that CD141/CD1c double negative myeloid dendritic cell(DNmDC)/lymphocytes and monocytes(%)in P group(0.041[0.024,0.069])was significantly lower than that in NH group(0.270[0.135,0.407])and NA group(0.273[0.150,0.443]),and CD86 mean fluorescence intensity of DNmDCs in P group(1832.0[1484.0,2793.0])was significantly lower than that in NH group(4316.0[2958.0,5169.0])and NA group(3299.0[2534.0,4371.0]),Adjusted P all<0.001. Conclusion Reduced DNmDCs and impaired maturation may be associated with the onset of the plateau phase during intermittent interferon therapy in patients with chronic hepatitis B.

Humans ; Myocarditis/diagnostic imaging* ; Magnetic Resonance Imaging ; Myocardium ; Giant Cells

Humans ; Myocarditis/diagnostic imaging* ; Magnetic Resonance Imaging ; Myocardium ; Giant Cells

Objective To investigate the therapeutic effect and mechanism of Jianwei Xiaozhang Tablets on rats with precancerous lesions of gastric cancer(PLGC).Methods Forty male SD rats were randomly divided into the normal group,the model group,the folic acid group and the Jianwei Xiaozhang Tablets group,with 10 rats in each group.In addition to the normal group,the other three groups of rats were prepared by gavage with Ranitidine Aqueous Solution combined with N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)solution drinking method for the preparation of PLGC model.After successful modeling,drugs were administered accordingly for 7 weeks.The changes in body mass of rats during modeling and drug administration were recorded,the gross view of the stomach was observed and scored pathologically,the coefficients of spleen and liver were determined,the pathological changes in gastric tissue were observed by hematoxylin-eosin(HE)staining,enzyme-linked immunosorbent assay(ELISA)was used to measure serum gastrin(GAS),motilin(MTL)and glucagon(GC),Alisin Blue-Periodic Acid Schiff's(AB-PAS)staining was used to observe the thickness of the mucosal layer of gastric tissues,the expressions of phosphatidylinositol 3-kinase(PI3K),phosphorylated PI3K(p-PI3K),protein kinase B(Akt),phosphorylated Akt(p-Akt),and endothelial-type nitric oxide synthase(eNOS)proteins in gastric tissues were detected by protein immunoblotting(Western Blot),and the expression of vascular endothelial growth factor A(VEGFA)protein in gastric tissues was detected by immunofluorescence staining.Results Compared with the normal group,the body mass of rats in the model group grew slowly during the experimental period,gastric macroscopic pathological scores were significantly increased(P＜0.01),splenic coefficient and hepatic coefficient were significantly decreased(P＜0.01),the gastric tissues showed cuprocyte hyperplasia and intestinal chemotaxis,gastric tissues'inflammation scores were significantly increased(P＜0.01),the serum GAS content was significantly increased(P＜0.01),and the MTL,GC contents were significantly reduced(P＜0.05),and the thickness of the mucous membrane layer of gastric tissue was significantly reduced(P＜0.05),the protein expression levels of PI3K,p-PI3K,Akt,p-Akt and eNOS were reduced(P＜0.01),and the protein expression level of VEGFA was reduced(P＜0.01);compared with the model group,the above indexes of the Jianwei Xiaozhang Tablets group and the folic acid group were all significantly improved(P＜0.05 or P＜0.01),among which,the Jianwei Xiaozhang Tablets group had a better improvement effect in the proliferation of cup cells and intestinal chemotaxis in gastric tissues,the content of serum GAS,and the thickness of the mucous layer in gastric tissues.Conclusion The mechanism of the improvement of PLGC in rats by Jianwei Xiaozhang Tablets may be related to the activation of the PI3K-Akt-eNOS pathway,which in turn promotes the angiogenesis and repair of gastric damaged tissues.

Objective To observe the regulatory mechanism of drug-containing serum of Jinghou Zengzhi Prescription based on qi and blood replenishing method on the expression of growth and differentiation factor 9(GDF9)and apoptosis of ovarian granulosa cells in rats with controlled ovarian hyperstimulation(COH).Methods Serum of COH rats(blank serum)and serum of COH rats gavaged by the Jinghou Zengzhi Prescription were prepared.A COH rat model was established and ovarian granulosa cells were collected.The experiment was divided into 5 groups:blank serum group,drug-containing serum group,drug-containing serum+SB203580[p38 mitogen-activated protein kinase(p38MAPK)inhibitor]group,drug-containing serum + PDTC[nuclear transcription factor κB(NF-κB)inhibitor]group,drug-containing serum + SB203580 + PDTC group.The mRNA expression levels of p38MAPK,casein kinase 2(CK2),nuclear transcription factor κB inhibitor α(IκBα),NF-κB and GDF9 were detected by real-time quantitative polymerase chain reaction(qRT-PCR),and GDF9 protein expression level was detected by Western Blot,and ovarian granulosa cell apoptosis was detected by terminal-deoxynucleoitidyl transferase mediated nick end labeling(TUNEL).Results The drug-containing serum of Jinghou Zengzhi Prescription decreased the mRNA expressions of p38MAPK and NF-κB,elevated the mRNA expressions of CK2 and IκBα,increased the mRNA and protein expression levels of GDF9,and decreased the apoptosis rate of ovarian granulosa cells in COH rats.The addition of p38MAPK inhibitor SB203580 alone and the addition of NF-κB inhibitor PDTC alone both promoted the mRNA and protein expressions of GDF9 and reduced the apoptosis rate of granulosa cells.Conclusion The drug-containing serum of Jinghou Zengzhi Prescription based on qi and blood replenishing method can promote the expression of GDF9 and inhibit the apoptosis of ovarian granulosa cells in rats with COH,and its mechanism may be related to the regulation of the expression of genes of the dual signaling pathways of p38MAPK and NF-κB.

Objective To compare the prevention and control effects of binocular myopia after wearing orthokeratology lenses or glasses for correction in adolescents with low-to-moderate unilateral myopia.Methods The clinical data of 46 adolescents with unilateral myopia treated in First Affiliated Hospital of Army Medical University were retrospectively analyzed,the patients were divided into the orthokeratology lenses group and spectacles group according to the correction methods,with 23 cases in each group.The axial length(AL),changes in spherical diopter(SD)and anisometropia between the myopic eye and the control eye with orthokeratology lenses spectacles for unilateral myopia correction,and orthokeratology lenses for unilateral and binocular myopia were compared.Results There was no significant difference in baseline AL,SD or anisometropia between the two groups(P>0.05).One year after unilateral myopia correction,the increase of SD for the myopic eye in the orthokeratology lenses group was less than that in the spectacles group(P<0.05),and there was no significant difference in the AL elongation of myopic eyes between the two groups(P>0.05);the elongation of AL for the control eyes in the orthokeratology lenses group was more than that in the spectacles group;the increase of SD for the myopic eyes in the orthokeratology lens group was lower than that in the spectacles group(P<0.05),and there was no significant difference in the increase of SD for the control eyes between the two groups(P>0.05);the anisometropia of patients in the orthokeratology lenses group was less than that in the spectacles group(P<0.05).The biological parameters of the eyes before and after wearing orthokeratology lenses in the patients with monocular and binocular myopia in the orthokeratology lens group were compared,the elongation of AL for the myopic eyes with lens in one eye was less than that with lenses in both eyes(P<0.05),and the elongation of AL for the control eye was more than that with lenses in both eyes(P<0.05),the increases of SD in both myopic eyes and control eyes were more than those with lenses in both eyes(P<0.05),and the anisotropia was more than that with lenses in both eyes(P<0.05).Conclusion Orthokeratology lenses is better than spectacles in controlling the increase of myopia in low-to-moderate unilateral myopia,which can reduce anisometropia between eyes.However,the AL of the emmetropic eye increases rapidly during unilateral myopia correction by orthokeratology lenses,and the progression of binocular myopia can be significantly delayed after wearing orthokeratology lenses.