Acute kidney injury (AKI) is a common clinically critical syndrome in hospitalized patients with high morbidity and mortality. At present, the mechanism of AKI has not been fully elucidated, and no therapeutic drugs exist. As known, glycolytic product lactate is a key metabolite in physiological and pathological processes. The kidney is an important gluconeogenic organ, where lactate is the primary substrate of renal gluconeogenesis in physiological conditions. During AKI, altered glycolysis and gluconeogenesis in kidneys significantly disturb the lactate metabolic balance, which exert impacts on the severity and prognosis of AKI. Additionally, lactate-derived posttranslational modification, namely lactylation, is novel to AKI as it could regulate gene transcription of metabolic enzymes involved in glycolysis or Warburg effect. Protein lactylation widely exists in human tissues and may severely affect non-histone functions. Moreover, the strategies of intervening lactate metabolic pathways are expected to bring a new dawn for the treatment of AKI. This review focused on renal lactate metabolism, especially in proximal renal tubules after AKI, and updated recent advances of lactylation modification, which may help to explore potential therapeutic targets against AKI.
Humans ; Acute Kidney Injury/metabolism* ; Lactic Acid/metabolism* ; Animals ; Glycolysis/physiology* ; Gluconeogenesis/physiology* ; Kidney/metabolism*

OBJECTIVE: To evaluate the advantages and limitations of transcutaneous electrical acupoint stimulation (TEAS) in the treatment of patients with severe gastrointestinal function injury in intensive care unit (ICU) by analyzing dynamic changes of intestinal fatty acid binding protein (I-FABP), D-lactic acid and citrulline. METHODS: A prospective single-center randomized controlled trial was conducted. Patients with severe gastrointestinal function injury admitted to the ICU from February 2021 to January 2024 were enrolled [age > 18 years old, acute gastrointestinal injury (AGI) grade 2 to 3, stable hemodynamics]. Patients with different AGI grades were randomly assigned in a 1:1 ratio to the TEAS group and the control group using simple randomization. Both groups received conventional treatment and enteral nutrition (EN). In addition, the TEAS group underwent TEAS at the Neiguan and Zusanli points for 30 minutes per session, twice daily for 7 days. Baseline data, including age, gender, underlying diseases, and primary diagnoses, were recorded. Three intestinal biomarkers, such as I-FABP, D-lactic acid, and citrulline were measured before and after 7 days of treatment. EN tolerance indicators and 28 days survival status were documented. The differences in various indicators were compared between the two groups, subgroup analyses were conducted based on AGI grading, and interaction between AGI grade and TEAS were analyzed. The 28-day Kaplan-Meier survival curves were generated for both groups. RESULTS: Finally, 133 patients were included, with 68 in the TEAS group and 65 in the control group. Baseline characteristics were comparable between the two groups. A comparison of the dynamic changes in intestinal biomarkers revealed that the I-FABP level in both groups decreased after treatment compared to pre-treatment, with a more pronounced reduction in the TEAS group. The least square mean difference (LS Mean difference) for the corrected I-FABP level between the two groups during the observation period was -0.23 μg/L [95% confidence interval (95%CI) was -0.45 to -0.01], which was statistically significant (P = 0.041). Additionally, a significant interaction with AGI was observed (P = 0.004). Post-treatment, D-lactic acid level decreased in both groups compared to pre-treatment, with a more significant reduction in the TEAS group. The LS Mean difference for the corrected D-lactic acid level was -0.08 mmol/L (95%CI was -0.11 to -0.05), which was statistically significant (P < 0.001), and the interaction with AGI was also significant (P = 0.005). There was no significant change in citrulline levels between the two groups before and after treatment. The LS Mean difference for the corrected citrulline level was -0.17 μmol/L (95%CI was -1.87 to 1.53), which was not statistically significant (P = 0.845), and no significant interaction with AGI was observed (P = 0.913). Comparison of EN tolerance parameters between the two groups revealed that the TEAS group had a longer total EN time (hours: 72±31 vs. 60±28) and higher total EN calories (kJ: 11 469.23±7 237.34 vs. 6 638.76±5 098.37), as well as a higher 70% target caloric attainment rate (52.9% vs. 32.3%) compared to the control group (all P < 0.05). The incidence of abdominal distension after EN was lower in the TEAS group than that in the control group (23.5% vs. 43.1%, P < 0.05), while the incidence of diarrhea after EN was higher in the TEAS group (22.1% vs. 7.7%, P < 0.05). There were no significantly differences in AGI grade reduction rate, post-EN vomiting/gastric retention rate, incidence of feeding interruption, and 28-day survival rate between the two groups. Furthermore, there were no significantly interaction between these observation measures and AGI. Kaplan-Meier survival analysis showed that there was no significantly difference in 28-day cumulative survival rate between the TEAS group and the control group [Log-Rank test: P = 0.501, hazard ratio (HR) = 0.81, 95%CI was 0.43-1.51), and there was no significantly interaction with AGI (P = 0.702). CONCLUSIONS The advantage of TEAS in the treatment of ICU patients with severe gastrointestinal function injury lies in its ability to reverse intestinal cell necrosis and promote the reconstruction of intestinal barrier function. Additionally, gastrointestinal tolerance is significantly improved, and both the duration and total calories of EN are increased. However, the limitation of TEAS therapy is that it does not promote the recovery of intestinal cell absorption and synthesis function in the target patients. Moreover, it may lead to nutrient solution overload due to improved gastrointestinal tolerance. Furthermore, TEAS does not appear to improve 28-day cumulative survival rate in the target patients.
Humans ; Prospective Studies ; Intensive Care Units ; Acupuncture Points ; Fatty Acid-Binding Proteins/metabolism* ; Transcutaneous Electric Nerve Stimulation ; Male ; Female ; Citrulline/metabolism* ; Lactic Acid/metabolism* ; Gastrointestinal Diseases/therapy* ; Middle Aged ; Enteral Nutrition ; Adult

OBJECTIVE: To explore the predictive efficacy of the early lactic acid/albumin ratio (LAR) for the occurrence of acute skin failure (ASF) in patients with sepsis. METHODS: A retrospective study was conducted to collect the clinical data of 115 patients with sepsis admitted to the intensive care unit (ICU) of the First Affiliated Hospital of Dalian Medical University from June 2022 to March 2024. The patients' gender, age, length of ICU stay, past medical history, and severity scores, use of mechanical ventilation or vasoactive drugs, albumin (Alb), lactic acid (Lac), mean arterial pressure (MAP), and blood gas analysis indicators within 24 hours of ICU admission were collected, and LAR was calculated. The patients were divided into two groups based on whether they developed ASF, and the clinical data between the two groups were compared. Multivariate Logistic regression analysis was used to screen the risk factors for the occurrence of ASF in patients with sepsis. The receiver operator characteristic curve (ROC curve) was drawn to analyze the predictive value of LAR for the occurrence of ASF in patients with sepsis. RESULTS: A total of 115 patients with sepsis were enrolled in the final analysis, among whom 35 developed ASF and 80 did not. The incidence of ASF was 30.43%. Univariate analysis showed that compared with the non-ASF group, the ASF group had higher acute physiology and chronic health evaluation II (APACHE II) score, proportion of using vasoactive drugs, Lac, and LAR as well as lower Alb and MAP, with statistically significant differences. Multivariate Logistic regression analysis was conducted on the factors with statistical significance in the univariate analysis, and the results showed that Alb [odds ratio (OR) = 0.639, 95% confidence interval (95%CI) was 0.474-0.862, P = 0.003], Lac (OR = 17.228, 95%CI was 1.517-195.641, P = 0.022), MAP (OR = 0.905, 95%CI was 0.855-0.959, P = 0.001), and LAR (OR < 0.001, 95%CI was < 0.001-0.005, P = 0.033) were independent risk factors for the occurrence of ASF in patients with sepsis. ROC curve analysis showed that the area under the ROC curve (AUC) of LAR for predicting the occurrence of ASF in patients with sepsis was 0.867 (95%CI was 0.792-0.943), which was superior to Alb, Lac, and MAP [AUC (95%CI) was 0.739 (0.648-0.829), 0.844 (0.760-0.929), and 0.860 (0.783-0.937), respectively]. When the optimal cut-off value of LAR was 0.11, the sensitivity was 65.7%, the specificity was 96.3%, and the Youden index was 0.620. Patients were grouped based on the optimal cut-off value of LAR, and the results showed that the incidence of ASF in the LAR > 0.11 group was significantly higher than that in the LAR ≤ 0.11 group [88.89% (24/27) vs. 12.50% (11/88), P < 0.05]. CONCLUSIONS LAR has early predictive value for the occurrence of ASF in patients with sepsis, and its efficacy is superior to that of Lac or Alb alone.
Humans ; Sepsis/blood* ; Retrospective Studies ; Lactic Acid/blood* ; Male ; Female ; Intensive Care Units ; Middle Aged ; Risk Factors ; Predictive Value of Tests ; Serum Albumin/analysis* ; ROC Curve ; Aged

OBJECTIVE: To investigate the predictive value of sphinor kinase 1 (sphk1), D-lactic acid, and intestinal fatty acid binding protein (I-FABP) for gastrointestinal injury in patients with sepsis. METHODS: A prospective observational study was conducted. Sixty-eight patients with sepsis and gastrointestinal dysfunction admitted to the department of critical care medicine of the First Affiliated Hospital of Baotou Medical College Inner Mongolia University of Science and Technology from May 2024 to March 2025 were enrolled (sepsis group), and they were divided into acute gastrointestinal injury (AGI) I-IV groups according to the definition and grading criteria of AGI proposed by the European Society of Intensive Care Medicine in 2012. Twenty non-sepsis patients without AGI admitted to the intensive care unit during the same period were enrolled as the control group (non-sepsis group). Within 30 minutes of patient enrollment, plasma sphk1, D-lactic acid, and I-FABP levels were determined by enzyme linked immunosorbent assay (ELISA). General data such as gender, age were recorded, and levels of procalcitonin (PCT), high-sensitivity C-reactive protein (hs-CRP), lactic acid (Lac), and acute physiology and chronic health evaluation II (APACHEII), sequential organ failure assessment (SOFA) were measured. Spearman method was used to analyze the correlation between sphk1, I-FABP, D-lactic acid and other indicators. The receiver operator characteristic curve (ROC curve) was used to evaluate the predictive value of sphk1, D-lactic acid, I-FABP, APACHEII score, and SOFA score for gastrointestinal injury in patients with sepsis. RESULTS: Among the 68 sepsis patients, 13 were classified as AGI grade I, 16 as AGI grade II, 23 as AGI grade III, and 16 had AGI grade IV. There were no statistically significant differences in gender, age, and abdominal infection rate among the groups. The SOFA score and APACHEII score of the sepsis group were significantly higher than those of the non-sepsis group; and the APACHEII score of the AGI IV group was significantly higher than that of the AGI I and AGI II groups. The levels of sphk1, D-lactic acid, I-FABP, PCT, Lac and hs-CRP in the sepsis group were significantly higher than those in the non-sepsis group, and each indicator gradually increased with the increase of AGI grade. Correlation analysis showed that plasma sphk1, D-lactic acid, and I-FABP in patients with sepsis-induced gastrointestinal injury were positively correlated with PCT, Lac, APACHEII score, and AGI grade (all P < 0.05), and sphk1 was positively correlated with I-FABP and D-lactic acid (r values were 0.773 and 0.782, respectively, both P < 0.05). ROC curve analysis showed that sphk1, D-lactic acid, I-FABP, APACHEII score, and SOFA score had high predictive value for gastrointestinal injury in patients with sepsis, with area under the curve (AUC) of 0.996, 0.987, 0.976, 0.901, and 0.934 (all P < 0.05). When the optimal cut-off value of sphk1 was 60.46 ng/L, the sensitivity and specificity were 95.6% and 100%, respectively; when the optimal cut-off value of D-lactic acid was 1 454.3 μg/L, the sensitivity and specificity were 95.6% and 100%, respectively; when the optimal cut-off value of I-FABP was 0.91 ng/L, the sensitivity and specificity were 95.6% and 100%, respectively; when the optimal cut-off value of APACHEII score was 14.5, the sensitivity and specificity were 80.9% and 85.0%, respectively; when the optimal cut-off value of SOFA score was 3.5, the sensitivity and specificity were 85.3% and 95.0%, respectively. CONCLUSIONS The levels of plasma sphk1, I-FABP, and D-lactic acid were significantly elevated in patients with sepsis and gastrointestinal injury. These indicators can serve as sensitive and relatively specific serological markers for early prediction of intestinal mucosal damage.
Humans ; Lactic Acid/blood* ; Fatty Acid-Binding Proteins/blood* ; Sepsis/complications* ; Prospective Studies ; Male ; Female ; Middle Aged ; Predictive Value of Tests ; Adult ; Aged ; Gastrointestinal Diseases/blood* ; Prognosis

In recent years, significant progress has been made in the study of the complex pathophysiology of sepsis. However, sepsis remains the main cause of high mortality among critically ill patients worldwide. Early diagnosis, timely treatment, and accurate prediction of the prognosis are crucial for the successful treatment of septic patients. Lactic acid not only serves as a diagnostic indicator for septic shock but also participates in the immune response process of sepsis. It regulates gene epigenetic regulation through lactylation, thereby affecting the expression of related genes, cellular metabolism, and the immune response of the body. Therefore, it may become a new target for the treatment of sepsis. Lactate-related indicators, such as lactic acid/albumin ratio (LAR) and lactic acid/hematocrit ratio (LHR), also have important value in the prognosis assessment of septic patients and are superior to the evaluation efficacy of a single indicator. This is of great significance for timely detection of the changes in the condition of septic patients and their risk stratification and precise treatment. This review focused on the relationship between lactylation, lactatization, lactate-related indicators and sepsis, as well as the latest research progress. By revealing their roles in the occurrence, development and prognosis of sepsis, it provided new ideas for clinical diagnosis and treatment, uncovered new mechanisms of disease onset, guided disease risk stratification, optimized existing treatment strategies, and also offered new references and directions for basic research on lactate-related indicators.
Humans ; Sepsis/metabolism* ; Lactic Acid/metabolism* ; Prognosis ; Biomarkers/blood*

The Chinese hamster ovary (CHO) cell is the most representative mammalian cell protein expression system, and it is widely used in recombinant protein, vaccine and other biopharmaceutical fields. However, due to its vulnerability to environmental factors, apoptosis, and metabolic inhibitors, CHO cells demonstrate poor robustness, and thus the integrated viable cell density and unit cell productivity are largely limited. To improve the robustness and foreign protein expression efficiency of CHO cells, we employed CRISPR/Cas9 to knock out the apoptosis genes Bax and Bak and the lactate dehydrogenase gene LDHa, thereby blocking apoptosis and lactic acid metabolism pathways. The results of apoptosis and single cell viability detection showed that the number of apoptotic cells in the knockout cell lines Bax^-/-, Bax-bak^-/-, and LDHa-Bax-bak^-/- was reduced by 22.51%, 37.73%, and 64.12%, respectively, compared with the wild-type cell line CHO-K1, which indicated that the anti-apoptotic ability was significantly improved. After staurosporine treatment, the single cell viability of Bax^-/-, Bax-bak^-/-, and LDHa-Bax-bak^-/- cells was increased by 30.8%, 22%, and 41.1%, respectively. After treatment with puromycin, the single cell viability of Bax^-/-, Bax-bak^-/-, and LDHa-Bax-bak^-/- cells was increased by 26.7%, 30.7%, and 38.8%, respectively. To further investigate the production performance of cells obtained after blocking apoptosis and lactic acid metabolism pathways, we induced transient expression of human tissue plasminogen activator (tPA) in these cells. The results showed that the secretion of tPA in Bax^-/-, Bax-Bak^-/-, and LDHa-Bax-Bak^-/- cells was 11.12%, 46.18%, and 63.13%, respectively, higher than that in wild-type CHO-K1 cells. The expression of intracellular tPA was increased by 35.65%, 130%, and 192.15%. In conclusion, blocking apoptosis and lactic acid metabolism pathways simultaneously can improve cell robustness and productivity, with the performance better than blocking the apoptosis pathway alone. The above results indicated that the constructed cell lines were expected to be the delivery carriers of protein drugs such as medicinal peptides, and better used for the treatment of diseases.
CHO Cells ; Cricetulus ; Animals ; Apoptosis/genetics* ; Lactic Acid/metabolism* ; Recombinant Proteins/biosynthesis* ; L-Lactate Dehydrogenase/genetics* ; bcl-2-Associated X Protein/genetics* ; bcl-2 Homologous Antagonist-Killer Protein/genetics* ; Cricetinae ; CRISPR-Cas Systems ; Staurosporine/pharmacology*

Blood biochemical indicators are an important basis for the diagnosis and treatment by doctors. The performance of related instruments, the qualification of operators, the storage method and time of blood samples and other factors will affect the accuracy of test results. However, it is difficult to meet the clinical needs of rapid detection and early screening of diseases with currently available methods. Point-of-care testing (POCT) is a new diagnostic technology with the characteristics of instant, portability, accuracy and efficiency. Microfluidic chips can provide an ideal experimental reaction platform for POCT. This paper summarizes the existing detection methods for common biochemical indicators such as blood glucose, lactic acid, uric acid, dopamine and cholesterol, and focuses on the application status of POCT based on microfluidic technology in blood biochemistry. It also summarizes the advantages and challenges of existing methods and prospects for development. The purpose of this paper is to provide relevant basis for breaking through the technical barriers of microfluidic and POCT product development in China.
Humans ; Point-of-Care Testing ; Lactic Acid/blood* ; Microfluidic Analytical Techniques/methods* ; Blood Glucose/analysis* ; Point-of-Care Systems ; Blood Chemical Analysis/instrumentation* ; Uric Acid/blood* ; Cholesterol/blood* ; Dopamine/blood* ; Microfluidics/methods*

OBJECTIVE: To summarize the biomechanical research progress of biomaterials in rotator cuff injury repair and to explore how biomaterials can restore the native histological and mechanical properties of the rotator cuff. METHODS: The relevant literature at home and abroad was widely reviewed to analyze the biomechanical properties of synthetic biomaterials, naturally derived biomaterials, and tissue grafts in the repair of rotator cuff injuries. RESULTS: Synthetic biomaterials [such as poly (lactic-co-glycolic acid) and polycaprolactone] can provide initial stable mechanical support due to their adjustable mechanical properties and degradation characteristics, while naturally derived biomaterials (such as collagen and hyaluronic acid) can promote cell adhesion and tissue integration due to their biocompatibility and bioactivity. Tissue grafts exhibit significant clinical utility by providing immediate mechanical stability and promoting tendon-to-bone healing. Three-dimensional bioprinting technology provides new possibilities for personalized repair of rotator cuff injuries by precisely controlling the spatial distribution and mechanical properties of biomaterials. CONCLUSION Future studies should further optimize the design of bioprinting materials, cell sources, and scaffolds to achieve better mechanical properties and clinical efficacy of biomaterials in the repair of rotator cuff injuries.
Humans ; Rotator Cuff Injuries ; Biocompatible Materials/chemistry* ; Biomechanical Phenomena ; Tissue Scaffolds ; Rotator Cuff/surgery* ; Tissue Engineering/methods* ; Polyesters ; Polyglycolic Acid/chemistry* ; Hyaluronic Acid/chemistry* ; Collagen/chemistry* ; Lactic Acid/chemistry* ; Polylactic Acid-Polyglycolic Acid Copolymer ; Bioprinting ; Wound Healing ; Printing, Three-Dimensional ; Tendon Injuries/surgery*

OBJECTIVE: To explore the role of the natural compound hesperidin in glycolysis, the key ratelimiting enzyme, in colorectal cancer (CRC) cell lines. METHODS: In vitro, HCT116 and SW620 were treated with different doses of hesperidin (0-500 µmol/L), cell counting kit-8 and colone formation assays were utilized to detected inhibition effect of hesperidin on CRC cell lines. Transwell and wound healing assays were performed to detect the ability of hesperidin (0, 25, 50 and 75 µmol/L) to migrate CRC cells. To confirm the apoptotic-inducing effect of hesperidin, apoptosis and cycle assays were employed. Western blot, glucose uptake, and lactate production determination measurements were applied to determine inhibitory effects of hesperidin (0, 25 and 50 µmol/L) on glycolysis. In vivo, according to the random number table method, nude mice with successful tumor loading were randomly divided into vehicle, low-dose hesperidin (20 mg/kg) and high-dose hesperidin (60 mg/kg) groups, with 6 mice in each group. The body weights and tumor volumes of mice were recorded during 4-week treatment. The expression of key glycolysis rate-limiting enzymes was determined using Western blot, and glucose uptake and lactate production were assessed. Finally, protein interactions were probed with DirectDIA Quantitative Proteomics, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. RESULTS: Hesperidin could inhibit CRC cell line growth (P<0.05 or P<0.01). Moreover, hesperidin presented an inhibitory effect on the migrating abilities of CRC cells. Hesperidin also promoted apoptosis and cell cycle alterations (P<0.05). The immunoblotting results manifested that hesperidin decreased the levels of hexokinase 2, glucose transporter protein 1 (GLUT1), GLUT3, L-lactate dehydrogenase A, 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 2 (PFKFB2), PFKFB3, and pyruvate kinase isozymes M2 (P<0.01). It remarkably suppressed tumor xenograft growth in nude mice. GO and KEGG analyses showed that hesperidin treatment altered metabolic function. CONCLUSION Hesperidin inhibits glycolysis and is a potential therapeutic choice for CRC treatment.
Hesperidin/therapeutic use* ; Colorectal Neoplasms/metabolism* ; Glycolysis/drug effects* ; Animals ; Humans ; Apoptosis/drug effects* ; Mice, Nude ; Cell Movement/drug effects* ; Cell Line, Tumor ; Cell Proliferation/drug effects* ; Glucose/metabolism* ; Cell Cycle/drug effects* ; Mice, Inbred BALB C ; Mice ; HCT116 Cells ; Lactic Acid

Lactic acid (LA) accumulation in tumor microenvironments (TME) has been implicated in immune suppression and tumor progress. Diverse roles of LA have been elucidated, including microenvironmental pH regulation, signal transduction, post-translational modification, and metabolic remodeling. This review summarizes LA functions within TME, focusing on the effects on tumor cells, immune cells, and stromal cells. Reducing LA levels is a potential strategy to attack cancer, which inevitably affects the physiological functions of normal tissues. Alternatively, transporting LA into the mitochondria as an energy source for immune cells is intriguing. We underscore the significance of LA in both tumor biology and immunology, proposing the burning of LA as a potential therapeutic approach to enhance antitumor immune responses.
Humans ; Tumor Microenvironment/immunology* ; Neoplasms/therapy* ; Lactic Acid/immunology* ; Mitochondria/metabolism* ; Animals ; Signal Transduction