1.Skeleton Binding Protein 1 of Plasmodium berghei Influences Deformability and Cytoskeletal Ultrastructure of Infected Erythrocyte
Xin-Yue GUO ; Huan-Qi ZHAO ; Yan-Xuan ZHONG ; Ru-Meng JIANG ; Yao-Xian LI ; Lei-Ting PAN ; Qian WANG ; Xiao-Yu SHI
Progress in Biochemistry and Biophysics 2026;53(4):1015-1027
ObjectiveThe malaria parasites remodel the host erythrocyte structure by exporting parasite proteins that interact with the membrane skeleton proteins of red blood cells (RBCs), facilitating their intracellular survival and pathogenicity. Skeleton-binding protein 1 (SBP1) is a conserved exported protein across Plasmodium species. In Plasmodium falciparum, SBP1 has been reported to interact with erythrocyte membrane skeleton proteins 4.1R and spectrin, while its contribution to erythrocyte remodeling and parasite virulence in Plasmodium berghei (Pb) remains unclear. This study aims to determine whether PbSBP1 associates with the host cytoskeletal protein 4.1R and to investigate its role in the remodeling of host RBCs and the pathogenicity of Plasmodium berghei. MethodsIn Plasmodium berghei, the relationship between PbSBP1 and the erythrocyte cytoskeletal protein 4.1R was examined using co-immunoprecipitation. A Pbsbp1 gene knockout mutant of Plasmodium berghei (Pbsbp1∆) was generated based on the principle of double crossover homologous recombination. The deformability of erythrocytes infected with Pbsbp1∆ parasites was assessed using microfluidic methods. Microchannels with an array of cylindrical pillars were used to detect modifications in infected RBC deformability. The infected RBCs were squashed between the rows and recovered between the columns and the transit velocity (μm/s) of infected RBCs travelling through the microchannel was recorded. The component of the erythrocyte membrane skeleton junctional complex, tropomodulin (TMOD), was fluorescently labeled, and the cytoskeletal network of infected erythrocytes was imaged using super-resolution stochastic optical reconstruction microscopy (STORM) to analyze ultrastructural changes in the cytoskeleton of wild-type (WT) and Pbsbp1∆-infected erythrocytes. Actin-based junctional complexes were displayed as individual clusters by the labeled TMOD in the STORM images, and the cluster densities and distances between adjacent clusters of infected RBCs were calculated. Additionally, rodent malaria models (BALB/c mice) and experimental cerebral malaria models (C57BL/6 mice) were employed to monitor the growth of Pbsbp1∆ and WT parasites during the intraerythrocytic stage and their capacity to induce cerebral malaria in mice. ResultsPbSBP1 may participate in the remodeling of infected erythrocytes through direct or indirect interaction with the erythrocyte cytoskeletal protein 4.1R. Microfluidic assays revealed that the deformability of erythrocytes infected with Pbsbp1∆ parasites was significantly enhanced compared to those infected with WT parasites. STORM imaging further demonstrated that the ultrastructure of the erythrocyte cytoskeleton in Pbsbp1∆-infected cells was altered relative to that in WT-infected erythrocytes. The distances between nearest neighbors of clusters had a tendency to increase while the cluster densities were decreased in Pbsbp1∆-infected RBCs compared to WT-infected RBCs. Subsequent phenotypic analysis indicated that the growth rate of Pbsbp1∆ parasites during the intraerythrocytic stage was significantly slower than that of WT parasites, and their ability to induce cerebral malaria in mice was also attenuated. These findings suggest that PbSBP1 is involved in the remodeling of the erythrocyte membrane skeleton, likely through its direct or indirect interaction with protein 4.1R, thereby regulating the deformability of infected erythrocytes and influencing the pathogenicity of the blood-stage parasites. ConclusionThis study establishes a role for PbSBP1 in host erythrocyte remodeling and parasite virulence, providing new research strategies for the prevention and treatment of malaria.
2.Clinical efficacy of Huangkui capsules in the treatment of targeted drug-related proteinuria in patients with hepatocellular carcinoma
Miao LI ; Jia YUAN ; Chu LIU ; Maopei CHEN ; Xin XU ; Ningling GE ; Yi CHEN ; Lan ZHANG ; Rongxin CHEN ; Yan WANG
Chinese Journal of Clinical Medicine 2026;33(1):88-94
Objective To investigate the therapeutic effect of Huangkui capsules on targeted drug-related proteinuria in patients with hepatocellular carcinoma (HCC). Methods A retrospective analysis was conducted on clinical data of HCC patients with targeted drug-related proteinuria from June 2023 to December 2024 at Zhongshan Hospital, Fudan University. According to the treatment plan, patients were divided into the conventional treatment group and the Huangkui combination treatment group (Huangkui capsules combined with conventional treatment), and the clinical efficacy between the two groups was compared. The logistic regression analysis was used to identify the main factors affecting treatment efficacy. Results The Huangkui combination treatment group (n=29) showed a significantly higher overall effective rate (79.3% vs 42.3%, P=0.005), and an earlier proteinuria improvement (median time: 3 months vs 6 months, P=0.008) than the conventional treatment group (n=26) . The multivariate logistic regression analysis showed angiotensin-converting enzyme inhibitor (ACEI) or angiotensin Ⅱ receptor blocker (ARB) using (OR=0.190, 95%CI 0.045-0.808, P=0.025), targeted drug adjustment (OR=0.132, 95%CI 0.030-0.581, P=0.007), and Huangkui capsules using (OR=0.168, 95%CI 0.039-0.730, P=0.017) were protective factors for treatment efficacy of targeted drug-related proteinuria. Conclusions On the basis of conventional treatment, additive treatment with Huangkui capsules can alleviate targeted drug-related proteinuria faster and more effectively in HCC patients.
3.Quercetin Ameliorates Gouty Arthritis in Rats via ROS/NLRP3/IL-1β Signaling Pathway
Baowei FENG ; Yan WANG ; Chang LI ; Yujing ZHANG ; Dingxing FAN ; Xin LI
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(2):145-153
ObjectiveTo investigate the effect of quercetin on acute gouty arthritis (GA) in rats by inhibiting the reactive oxygen species (ROS)/NOD-like receptor protein 3 (NLRP3)/interleukin-1β (IL-1β) signaling pathway. MethodsSixty SPF-grade male SD rats were randomized into normal, model, colchicine (0.3 mg·kg-1), and low-, medium-, and high-dose (25, 50, 100 mg·kg-1, respectively) quercetin groups (n=10). The rats in the dosing groups were administrated with the corresponding drugs (10 mL·kg-1) by gavage once a day for one week. An equal volume of normal saline was given by gavage to rats in normal and model groups. One hour after drug administration on day 5, an acute GA model was established in other groups except the control group via intra-articular injection of monosodium urate (MSU) suspension into the right posterior ankle joint cavity. The joint swelling and gait were scored at the time points of 6, 12, 24, 48 h after modeling. Histopathological alterations in the ankle joint tissue from each group were assessed by hematoxylin-eosin (HE) staining. Malondialdehyde (MDA), xanthine oxidase (XOD), and total superoxide dismutase (T-SOD) assay kits were used to assess the levels of MDA, XOD, and T-SOD in the serum. The levels of tumor interleukin-6 (IL-6), necrosis factor-α (TNF-α), and IL-1β in the rat serum, as well as ROS in the ankle joint tissue, were measured by enzyme-linked immunosorbent assay (ELISA). Western blot was performed to determine the protein levels of NLRP3, thioredoxin-interacting protein (TXNIP), apoptosis-associated speck-like protein containing a CARD domain (ASC), precursor cysteinyl aspartate-specific proteinase-1 (pro-Caspase-1), cleaved Caspase-1 (Caspase-1 p20), and IL-1β in the ankle joint tissue. Real-time PCR was employed to assess the mRNA levels of TXNIP, NLRP3, ASC, IL-1β, and TNF-α in the ankle joint tissue. ResultsCompared with the normal group, the model group exhibited decreased spontaneous activity, mental fatigue, increased ankle joint swelling and gait scores (P<0.01), aggravated synovial tissue edema and inflammatory cell infiltration (P<0.01), elevated levels of XOD, MDA, TNF-α, IL-1β, and IL-6 in the serum and ROS in the joint tissue (P<0.01), a declined level of T-SOD (P<0.01), up-regulated protein levels of NLRP3, TXNIP, ASC, pro-Caspase-1, Caspase-1 p20, and IL-1β in the ankle joint tissue (P<0.01), and up-regulated mRNA levels of NLRP3, TXNIP, ASC, IL-1β, and TNF-α in the ankle joint tissue (P<0.01). Compared with the model group, the medium- and high-dose quercetin groups showed improved general conditions, decreased gait scores (P<0.05, P<0.01), reduced joint swelling (P<0.01), alleviated synovial tissue edema and inflammatory cell infiltration (P<0.05, P<0.01), lowered levels of XOD, MDA, TNF-α, IL-1β, and IL-6 in the serum and ROS in the joint tissue (P<0.01), increased levels of T-SOD (P<0.01), down-regulated protein levels of TXNIP, NLRP3, ASC, pro-Caspase-1, Caspase-1 p20, and IL-1β in the ankle joint tissue (P<0.05, P<0.01), and down-regulated mRNA levels of TXNIP, NLRP3, ASC, IL-1β, and TNF-α in the ankle joint tissue (P<0.01). Low-dose quercetin also ameliorated some of the above parameters (P<0.05, P<0.01). ConclusionQuercetin exerts anti-GA effects by blocking the ROS/NLRP3/IL-1β signaling pathway, downregulating NLRP3 inflammasome activation, and inhibiting the production of pro-inflammatory cytokines including TNF-α, IL-1β, and IL-6.
4.Exploring the pathogenesis and treatment methods of irritable bowel syndrome from the
Yan XU ; Fang YANG ; Rongshi SHAO ; Huili SUN ; Juan LI ; Xin CHEN ; Jing HAN
Journal of Beijing University of Traditional Chinese Medicine 2026;49(1):10-15
This article adopts Professor CHEN Chaozu′s " sanjiao composed by membrane-striae" theory as its foundation to explore the relationship between irritable bowel syndrome and functional/structural abnormalities of the membrane-striae. Sanjiao encompasses both the tangible membrane and the intangible striae. These striae permeate the entire body,and their pathological changes comprehensively reflect qi,body fluids,and fasciae. Based on the physiological function of the membrane-striae in regulating qi and fluids,the pathogenesis of irritable bowel syndrome is characterized by a disharmony of membrane-striae and an imbalance of the qi-fluid interactions. In the early stage,external pathogens,emotional factors,or dietary stimuli often cause membrane-striae constriction and disordered qi-fluid circulation. In the middle stage,stagnant fluids gradually transform into phlegm retention,leading to membrane-striae obstruction. In the late stage,deficiency of vital qi becomes predominant,manifesting as laxity of membrane-striae with impaired control or weakened conduction. The treatment of irritable bowel syndrome should adopt " unblocking" as the guiding principle. In the early stage,therapy should focus on eliminating pathogenic factors and soothing membrane-striae to promptly restore qi-fluid circulation,thereby attaining unblocking through spasm relief. In the middle stage,treatment should focus on resolving tangible obstructions in membrane-striae,achieving unblocking via dredging. In the late stage,the emphasis should shift to reinforcing healthy qi,particularly by strengthening spleen-kidney yang qi,and achieving unblocking through supplementation. Concurrently,throughout the entire treatment process,the regulation of mental state and easing of emotional tension should be integrated to alleviate patient′s anxiety,achieving the goal of holistic treatment of both body and mind.
5.Expert consensus on the clinical application of parenteral direct thrombin inhibitors in special populations
Xin YAO ; Yuan BIAN ; Lizhu HAN ; Qinan YIN ; Yang LEI ; Zimeng WAN ; Luyao HUANG ; Danjie ZHAO ; Yu YAN ; Qin LI ; Baorong HU
China Pharmacy 2026;37(8):965-975
OBJECTIVE To form an expert consensus addressing clinical issues regarding the use of parenteral direct thrombin inhibitors (DTIs) in special populations. METHODS Led by the Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital(the Affiliated Hospital of UESTC), a multidisciplinary working group was formed comprising experts from multiple fields, including clinical pharmacy, cardiac surgery, obstetrics, pediatrics and evidence-based medicine. Through literature review and the Delphi method, clinical questions regarding the efficacy and safety of parenteral DTIs used in special populations were identified. A structured design was adopted using the “Population-Intervention-Comparison-Outcome” (PICO) framework;systematic searches were conducted in CJFD, PubMed, Embase and other databases. Relevant evidence from randomized controlled trials,cohort studies and systematic reviews were included and synthesized. Evidence quality was assessed using the Grading of Recommendations Assessment,Development and Evaluation (GRADE) approach, and recommendations were formulated through three rounds of Delphi surveys and expert consensus meetings. RESULTS &CONCLUSIONS Seven clinical questions were ultimately selected (with a consensus rate exceeding 90%), resulting in the formulation of seven recommendations on the use of parenteral DTIs in special populations, including children, pregnant women, patients with hepatic or renal impairment, patients with mesenteric venous thrombosis, and individuals with thrombophilia. These recommendations clarify the preferred agents, dosing ranges, monitoring parameters, and safety management strategies for parenteral DTIs in these special populations. This expert consensus, which is formulated based on the best available evidence, provides evidence-based guidance for standardized and individualized use of parenteral DTIs in special populations.
6.Exploring Mechanism of Hei Xiaoyaosan Regulating PI3K/Akt Pathway to Improve Learning and Memory Ability of Insomnia Rats with Liver Depression Syndrome Based on Transcriptomics
Jiamin LIU ; Yale WANG ; Hai HUANG ; Yue LI ; Xin FAN ; Pengpeng LIANG ; Shizhao ZHANG ; Mei YAN ; Guiyun LI ; Hongyan WU
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(16):114-125
ObjectiveBased on transcriptomics, to explore the mechanism of Hei Xiaoyaosan regulating the phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) signaling pathway to improve the learning and memory ability of insomnia rats with liver depression syndrome. MethodsSixty 8-week-old male SD rats were randomly divided into the blank group, model group, eszopiclone group (0.09 mg·kg-1), and low, medium, and high dose groups of Hei Xiaoyaosan (3.82, 7.65, 15.30 g·kg-1), with ten rats in each group. Except for the blank group, the other groups were induced insomnia rat model with liver depression by chronic restraint, tail clamping stimulation and intraperitoneal injection of p-chlorophenylalanine (PCPA). Each treatment group received intragastric administration according to the specified dosage, once a day for 14 consecutive days. The pentobarbital sodium cooperative sleep test, open field test, and Morris water maze test were used to test the sleep quality, depressive-like behavior, and learning and memory abilities of rats. Additionally, enzyme-linked immunosorbent assay (ELISA) was used to detect the contents of 5-hydroxytryptamine (5-HT), γ-aminobutyric acid (GABA), brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF) and nitric oxide (NO) in hippocampus. Hematoxylin-eosin (HE) staining was performed to observe pathological changes of the hippocampal tissue, while terminal deoxynucleotidyl transferase deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) was used to evaluate apoptosis of hippocampal neurons. Transcriptomic sequencing technology was employed to identify differentially expressed genes in hippocampus between the model group and the blank group, as well as between the medium-dose group of Hei Xiaoyaosan and the model group. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were performed on the intersecting genes. Subsequently, the enriched key genes and signaling pathways were analyzed and verified. Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR) was utilized to assess the mRNA expression levels of phosphatase and tensin homolog (PTEN), B-cell lymphoma-2 (Bcl-2)-like protein 11 (BCL2L11), and mitogen-activated protein kinase 1 (MAPK1) in hippocampus, and Western blot was employed to evaluate the protein expressions of PI3K, phosphorylation (p)-PI3K, Akt, p-Akt, Bcl-2, Bcl-2-associated X protein (Bax), and cleaved Caspase-3 in the same tissue. ResultsCompared with the blank group, the model group exhibited a reduction in body weight, an increase in sleep latency, and a decrease in sleep duration (P<0.01). Additionally, rats showed obvious depression-like behavior, and their learning and memory abilities decreased. Furthermore, the contents of 5-HT, GABA, NO, BDNF and GDNF in hippocampus decreased (P<0.01). Histological examination revealed a disorganized cell arrangement in the CA1 region of the hippocampus, characterized by irregular cell shapes, a reduced cell count, deeply stained and pyknotic nuclei, increased vacuolar degeneration, and an elevated apoptosis rate (P<0.01). Compared with the model group, the body weight of the high and medium dose groups of Hei Xiaoyaosan increased, the sleep latency shortened and the sleep time prolonged (P<0.05, P<0.01). Additionally, depression-like behavior and learning and memory abilities of rats were significantly improved, the levels of 5-HT, GABA, NO, BDNF and GDNF in the hippocampus increased (P<0.05, P<0.01). These interventions also ameliorated pathological damage in the hippocampal CA1 area and reduced the apoptosis of hippocampal neurons (P<0.01). Transcriptomic sequencing results indicated that Hei Xiaoyaosan might exert a therapeutic effect by regulating PI3K/Akt pathway through key mRNAs such as PTEN, BCL2L11, and MAPK1. The roles of these key mRNAs and proteins within PI3K/Akt pathway were further validated. In comparison to the blank group, the expression levels of PTEN, BCL2L11 and MAPK1 mRNA in the hippocampus of rats in the model group were increased (P<0.01), while the protein expression levels of p-PI3K, p-Akt and Bcl-2 were decreased (P<0.01), and the protein expression levels of PTEN, Bax and cleaved Caspase-3 were increased (P<0.01). Compared with the model group, the high-dose and medium-dose groups of Hei Xiaoyaosan could down-regulate the expressions of PTEN, BCL2L11 and MAPK1 mRNAs (P<0.01), up-regulate the expressions of p-PI3K, p-Akt and Bcl-2 proteins (P<0.01), and down-regulate the protein expressions of PTEN, Bax and cleaved Caspase-3 (P<0.05, P<0.01). ConclusionHei Xiaoyaosan may regulate PI3K/Akt signaling pathway by down-regulating expressions of key genes such as PTEN, BCL2L11 and MAPK1, and thus improve the learning and memory abilities of insomnia rats with liver depression syndrome.
7.Differential Analysis on Chemical Composition and Pharmacodynamic Effect Between Combined Decoction and Single Decoction of Famous Classical Formula Huaganjian
Yang WANG ; Gaoju ZHANG ; Ling LI ; Liping CHEN ; Li ZHANG ; Xiao LIU ; Yuyu ZHANG ; Yuan CUI ; Minglong LI ; Chaomei FU ; Xin YAN ; Yuxin HE ; Qin DONG
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(16):199-207
ObjectiveThrough qualitatively and quantitatively analysis of the differences in chemical composition between the combined decoction and single decoction of Huaganjian and comparison of their core efficacy, to explore the rationality of the flexible clinical application of Huaganjian compound preparations and single-flavored dispensing granules. MethodsUltra performance liquid chromatography-quadrupole-electrostatic field orbitrap high resolution mass spectrometry(UPLC-Q-Exactive Orbitrap MS) was used to qualitatively analyze the combined decoction and single decoction samples of Huaganjian, and meanwhile, the contents of four index components(geniposide, paeoniflorin, hesperidin and paeonol) were quantitatively analyzed by high performance liquid chromatography(HPLC). Nonalcoholic fatty liver disease(NAFLD) rat model induced by high-fat diet was applied to compare the efficacy of combined decoction and single decoction of Huaganjian. A total of 30 male SD rats were randomly divided into the control group, model group, lovastatin group(1.8 mg·kg-1), combined decoction group(1.26 g·kg-1) and single decoction group(1.18 g·kg-1). After successful modeling, lovastatin group, combined decoction group and single decoction group were given corresponding doses of drugs by intragastric administration every day, and the control group and model group were given equal amounts of normal saline by intragastric administration, after 4 weeks of administration, the serum and liver tissues were collected, and the contents of alanine aminotransferase(ALT), aspartate aminotransferase(AST), total cholesterol(TC), triglyceride(TG), low-density lipoprotein cholesterol(LDL-C) and high-density lipoprotein cholesterol(HDL-C) in serum of rats were detected, and the liver pathological examination was carried out by hematoxylin-eosin(HE) staining and oil red O staining, so as to compare differences of their efficacy. ResultsSeventy chemical components were initially identified and attributed from the lyophilized powder of the combined decoction and single decoction samples of Huaganjian, and there was no obvious difference in composition between the two. Further quantitative analysis showed that the contents of geniposide, paeoniflorin, hesperidin and paeonol in the combined decoction samples were significantly increased when compared with those of the single decoction samples(P<0.01). The pharmacodynamic results showed that compared with the model group, both the combined and single decoction groups of Huaganjian could improve the liver index of NAFLD rats, reduce the serum levels of AST, ALT, TC, TG and LDL-C, increase the serum level of HDL-C, and ameliorate the pathological changes of liver cell steatosis and fat accumulation. However, there was no significant difference in pharmacodynamic effects between the combined decoction group and the single decoction group. ConclusionThere is no significant difference between the combined decoction and single decoction of Huaganjian in terms of chemical composition, but the contents of the four index components show significantly difference. Both of them can significantly improve the fat accumulation and liver function in NAFLD rats. This study provides a reference basis for the rational clinical application and evaluation of famous classical formula compound preparations and single-flavored dispensing granules.
8.Research progress of acetylation in the pathogenesis of MASLD
Li YAN ; Fengyu JU ; Xin SHEN ; Ye YU ; Wenhui WANG
Journal of China Pharmaceutical University 2025;56(1):31-39
Metabolic dysfunction-associated steatotic liver disease (MASLD) is the most prevalent cause of chronic liver disease worldwide, and its intricate pathogenesis presents challenges in the development of new drugs. As a common way of post-translational modification, acetylation regulates protein stability, enzyme activity, and subcellular localization, occurring extensively in MASLD-associated processes such as lipid metabolism, inflammatory response, and oxidative stress. In this paper, we comprehensively review the mechanism of acetylation in MASLD, analyze the expression levels of acetylases in liver tissues of MASLD patients from the gene expression omnibus (GEO), discuss the changes in relevant enzyme expression and mechanisms in animal models, and further explore the feasibility of targeting acetylation for MASLD treatment, in the hope of offering a new perspective for advancing drug discovery in the field of MASLD.
9.Clinical application of blink reflex, video head impulse test, and vestibular myogenic evoked potentials in dizzy diseases
Yan LI ; Hong XIN ; Jiajia WANG
Journal of Apoplexy and Nervous Diseases 2025;42(2):155-158
Objective To investigate the clinical application value of blink reflex (BR), video head impulse test (vHIT), and vestibular evoked myogenic potentials (VEMP) in vertigo diseases. Methods A retrospective analysis was performed for the electrophysiological results of BR, vHIT, and VEMP in 80 patients with vertigo diseases, among whom there were 37 patients with posterior circulation ischemic isolated vertigo and 43 patients with acute vestibular neuritis, and the imaging findings of patients with posterior circulation ischemic isolated vertigo were also analyzed. Results For the post circulation ischemic isolated vertigo group, the positive rates of BR, vHIT, and VEMP were 75.6%, 0%, and 32.4%, respectively, and for the acute vestibular neuritis group, the positive rates of BR, vHIT, and VEMP were 18.6%, 88.4%, and 55.8%, respectively. Conclusion There is a relatively high positive rate of BR in posterior circulation ischemic isolated vertigo, and vHIT has good sensitivity and specificity in the diagnosis of acute vestibular neuritis, while VEMP can identify peripheral vestibular vertigo. As for the location of infarct lesions in the patients with posterior circulation ischemic isolated vertigo, the patients with cerebellar infarction account for the highest proportion, followed by those with brainstem infarction. The combined use of these three electrophysiological techniques can differentiate posterior circulation ischemic isolated vertigo from acute vestibular neuritis, thereby guiding the early differential diagnosis and treatment of posterior circulation ischemic isolated vertigo.
10.The Mesencephalic Locomotor Region for Locomotion Control
Xing-Chen GUO ; Yan XIE ; Xin-Shuo WEI ; Wen-Fen LI ; Ying-Yu SUN
Progress in Biochemistry and Biophysics 2025;52(7):1804-1816
Locomotion, a fundamental motor function encompassing various forms such as swimming, walking, running, and flying, is essential for animal survival and adaptation. The mesencephalic locomotor region (MLR), located at the midbrain-hindbrain junction, is a conserved brain area critical for controlling locomotion. This review highlights recent advances in understanding the MLR’s structure and function across species, from lampreys to mammals and birds, with a particular focus on insights gained from optogenetic studies in mammals. The goal is to uncover universal strategies for MLR-mediated locomotor control. Electrical stimulation of the MLR in species such as lampreys, salamanders, cats, and mice initiates locomotion and modulates speed and patterns. For example, in lampreys, MLR stimulation induces swimming, with increased intensity or frequency enhancing propulsive force. Similarly, in salamanders, graded stimulation transitions locomotor outputs from walking to swimming. Histochemical studies reveal that effective MLR stimulation sites colocalize with cholinergic neurons, suggesting a conserved neurochemical basis for locomotion control. In mammals, the MLR comprises two key nuclei: the cuneiform nucleus (CnF) and the pedunculopontine nucleus (PPN). Both nuclei contain glutamatergic and GABAergic neurons, with the PPN additionally housing cholinergic neurons. Optogenetic studies in mice by selectively activating glutamatergic neurons have demonstrated that the CnF and PPN play distinct roles in motor control: the CnF drives rapid escape behaviors, while the PPN regulates slower, exploratory movements. This functional specialization within the MLR allows animals to adapt their locomotion patterns and speed in response to environmental demands and behavioral objectives. Similar to findings in lampreys, the CnF and PPN in mice transmit motor commands to spinal effector circuits by modulating the activity of brainstem reticular formation neurons. However, they achieve this through distinct reticulospinal pathways, enabling the generation of specific behaviors. Further insights from monosynaptic rabies viral tracing reveal that the CnF and PPN integrate inputs from diverse brain regions to produce context-appropriate behaviors. For instance, glutamatergic neurons in the PPN receive signals from other midbrain structures, the basal ganglia, and medullary nuclei, whereas glutamatergic neurons in the CnF rarely receive inputs from the basal ganglia but instead are strongly influenced by the periaqueductal grey and inferior colliculus within the midbrain. These differential connectivity patterns underscore the specialized roles of the CnF and PPN in motor control, highlighting their unique contributions to coordinating locomotion. Birds exhibit exceptional flight capabilities, yet the avian MLR remains poorly understood. Comparative studies suggest that the pedunculopontine tegmental nucleus (PPTg) in birds is homologous to the mammalian PPN, which contains cholinergic neurons, while the intercollicular nucleus (ICo) or nucleus isthmi pars magnocellularis (ImC) may correspond to the CnF. These findings provide important clues for identifying the avian MLR and elucidating its role in flight control. However, functional validation through targeted experiments is urgently needed to confirm these hypotheses. Optogenetics and other advanced techniques in mice have greatly advanced MLR research, enabling precise manipulation of specific neuronal populations. Future studies should extend these methods to other species, particularly birds, to explore unique locomotor adaptations. Comparative analyses of MLR structure and function across species will deepen our understanding of the conserved and evolved features of motor control, revealing fundamental principles of locomotion regulation throughout evolution. By integrating findings from diverse species, we can uncover how the MLR has been adapted to meet the locomotor demands of different environments, from aquatic to aerial habitats.


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