ObjectiveTo investigate the mechanisms by which Huanglian Jiedutang （HLJDT） modulates microglial （MG） phenotypes through the sialic acid-binding Ig-like lectin 2 （SIGLEC2/CD22）/Src-homology-2-domain-containing protein tyrosine phosphatase-1 （SHP-1）/phosphorylated protein kinase B （p-Akt） signaling pathway， thereby promoting myelin repair and alleviating agitation-like behaviors in vascular dementia （VAD）. MethodsSixty C57BL/6J mice were randomly assigned to a sham （normal） group， model group， HLJDT low-， medium-， and high-dose groups （2.5， 5， and 10 g·kg^-1·d^-1）， and a risperidone group （2 mg·kg^-1·d^-1）， with 10 mice per group. VAD was induced by bilateral common carotid artery stenosis （BCAS）. From day 42， mice received drug interventions for 2 weeks. Agitation-like behaviors were assessed using the resident-intruder test. After behavioral testing， ventrolateral part of the ventromedial hypothalamus （VMHvl） tissues were collected. Western blot was used to measure protein levels of myelin oligodendrocyte glycoprotein （MOG）， myelin basic protein （MBP）， proteolipid protein （PLP）， inducible nitric oxide synthase （iNOS）， arginase-1 （Arg1）， CD86， CD206， and CD22， SHP-1， and p-Akt. Immunofluorescence was used to evaluate myelin-associated glycoprotein （MAG） intensity and the proportion of iNOS⁺/ionized calcium-binding adapter molecule 1 （Iba1）⁺ cells. ELISA was used to detect tumor necrosis factor-α （TNF-α）， interleukin （IL）-6， and IL-1β. ResultsCompared with the normal group， the model group exhibited markedly increased biting and aggressive behaviors and shortened attack latency （P<0.01）. MOG， MBP， and PLP protein levels and MAG fluorescence intensity were significantly reduced （P<0.05， P<0.01）. INOS and CD86 expression and TNF-α， IL-6， and IL-1β levels were significantly elevated （P<0.01）. CD22 and SHP-1 expression increased significantly （P<0.01）， whereas p-Akt expression decreased （P<0.01）. Compared with the model group， the medium- and high-dose HLJDT groups and the risperidone group showed markedly reduced biting and aggression （P<0.05， P<0.01） and prolonged attack latency （P<0.01）. MOG， MBP， and PLP levels and MAG fluorescence intensity were significantly increased （P<0.05， P<0.01）. INOS， CD86， TNF-α， IL-6， and IL-1β levels decreased significantly （P<0.05， P<0.01）. CD22 and SHP-1 expression decreased， while p-Akt expression increased significantly （P<0.05， P<0.01）. ConclusionHLJDT may modulate CD22/SHP-1/p-Akt signaling in the VMHvl， promote the shift of MG toward an anti-inflammatory and phagocytic phenotype， enhance myelin repair， and improve agitation-like behaviors in VAD mice.

ObjectiveTo explore the clinical efficacy and mechanism of Bupi Qingfei prescription （BPQF） in treating stable bronchiectasis in the patients with syndromes of lung-spleen Qi deficiency and phlegm-heat accumulation in the lungs. MethodsA randomized， double-blind， placebo-controlled trial was conducted. Patients were randomized into BPQF and placebo control （PC） groups. On the basis of conventional Western medicine treatment， the BPQF granules and placebo were respectively administered at 10 g each time， twice a day， for a course of 24 weeks. The TCM symptom scores， Quality of Life Questionnaire for Bronchiectasis （QOL-B） scores， lung function indicators， T lymphocyte subsets， level of inflammatory factors in the sputum， level of neutrophil elastase （NE） in the sputum， and occurrence of adverse reactions were observed before and after treatment in the two groups. ResultsA total of 64 patients completed the study， encompassing 32 in the BPQF group and 32 in the PC group. After treatment， the BPQF group showed decreased TCM symptom scores （P<0.01）， increased QOL-B scores （P<0.01）， and declined levels of tumor necrosis factor （TNF）-α and NE （P<0.05， P<0.01）. The PC group showed decreased TCM symptom （except spleen deficiency） scores （P<0.01）， increased the QOL-B health cognition and respiratory symptom domain scores （P<0.05， P<0.01）， and a declined TNF-α level （P<0.01）. Moreover， the BPQF group had lower TCM symptom （except chest tightness） scores （P<0.05， P<0.01）， higher QOL-B （except treatment burden） scores （P<0.05， P<0.01）， and lower levels of interleukin-6 and TNF-α （P<0.05） than the PC group. Neither group showed serious adverse reactions during the treatment process. ConclusionBPQF can ameliorate the clinical symptoms of stable bronchiectasis patients who have lung-spleen Qi deficiency or phlegm-heat accumulation in the lungs by regulating the immune balance and inhibiting airway inflammatory responses.

ObjectiveTo evaluate the clinical efficacy and safety of Jingmaiyan granules （composed of Lonicerae Japonicae Flos， Sedi Herba， Paeoniae Radix Rubra， Moutan Cortex， Rhei Radix et Rhizoma Praeparata， and Glycyrrhizae Radix et Rhizoma） combined with external application of Jinhuang Ointment in treating acute-stage blood heat stasis type superficial thrombophlebitis （ST） of lower extremities， and to explore their effects on hemorheology and serum inflammatory factors. MethodsA randomized， double-blind， placebo-controlled clinical trial was conducted. A total of 124 patients with lower extremity ST were randomized into two groups（62 cases in each group）. The control group received external application of Jinhuang ointment and oral placebo treatment， while the observation group received external application of Jinhuang ointment and oral Jingmaiyan granules. Both groups were treated for 2 weeks. The clinical symptom scores， therapeutic efficacy of traditional Chinese medicine （TCM） syndrome， pain visual analog scale （VAS） scores， hemorheological indices ［including whole blood high-shear， medium-shear， and low-shear viscosity， as well as plasma viscosity （PV）］， and inflammatory factors ［C-reactive protein （CRP）， interleukin-6 （IL-6）， tumor necrosis factor-α （TNF-α）］ were compared before and after treatment. ResultsAfter 2 weeks of treatment， the total effective rate in the observation group （98.3%， 60/62） was significantly higher than that in the control group （83.8%， 52/62）， with a statistically significant difference （Z=3.512 1， P<0.05）. Compared with pre-treatment scores， the scores for skin color， skin temperature， swelling， pain， and cord or nodules were significantly reduced in both groups （P<0.05）， with more pronounced improvement in the observation group （P<0.05）. Additionally， compared with pre-treatment levels， the whole blood viscosity （low-， medium-， and high-shear） significantly improved in both groups after treatment （P<0.05）， with more marked improvement in the observation group （P<0.05）. Furthermore， the plasma viscosity， CRP， IL-6， and TNF-α levels were significantly reduced in both groups after treatment （P<0.05）， with more pronounced improvement observed in the observation group （P<0.05）. ConclusionThe combination of external application of Jinhuang ointment and oral Jingmaiyan granules effectively improves clinical symptoms， hemorheological abnormalities， and inflammatory responses in patients with acute stage blood heat stasis type ST of lower extremities. The treatment is safe and holds clinical promotion value.

Chaihu Guizhi Ganjiangtang was first recorded in the Treatise on Cold Damage （Shang Han Lun）. This prescription is composed of Bupleuri Radix， Scutellariae Radix， Cinnamomi Ramulus， Zingiberis Rhizoma， Trichosanthis Radix， Ostreae Concha， and Glycyrrhizae Radix et Rhizoma. It has the effects of soothing Lesser Yang， warming the spleen， and stimulating the generation of body fluid. It is mainly used to treat digestive tract diseases such as chronic cholecystitis （CC）， irritable bowel syndrome， and non-alcoholic fatty liver disease. Dyspepsia caused by CC presents a variety of gastrointestinal symptoms such as abdominal pain， poor appetite， postprandial fullness， aversion to greasy food， soft stool， and bitter mouth， being a type of biliary dyspepsia. In modern medicine， dyspepsia caused by CC is mainly managed by medical treatment and surgical treatment. Internal medicine mainly focuses on reducing inflammation， promoting the function of gallbladder， resolving stones， alleviating spasms， and relieving the pain for CC， demonstrating definite short-term efficacy but suffering from single effects， high recurrence rate， and poor compliance. Although surgical treatment can cure cholecystitis， it is accompanied by the increased incidence of adverse events such as abdominal pain， diarrhea， and dyspepsia. Modern clinical studies have confirmed that Chaihu Guizhi Ganjiangtang can significantly alleviate the symptoms such as abdominal pain and dyspepsia of CC patients. Pharmacological studies have found that Chaihu Guizhi Ganjiangtang mainly contains active ingredients such as Bupleuri Radix saponins， baicalin， cinnamaldehyde， gingerol， Trichosanthis Radix polysaccharide， Ostreae Concha polysaccharide， and Glycyrrhizae Radix et Rhizoma total flavonoids. Chaihu Guizhi Ganjiangtang can ameliorate the symptoms of dyspepsia caused by CC by inhibiting inflammatory responses， improving gallbladder contraction and gastrointestinal motility， regulating the bile acid-intestinal flora axis and the brain-gut axis， and modulating blood lipids through multiple targets. By reviewing the previous literature， this article summarizes the research progress in the treatment of dyspepsia caused by CC with Chaihu Guizhi Ganjiangtang and its main active ingredients as well as the pathogenesis of this disease and puts forward the shortcomings and improvement strategies for the current research. The review aims to provide a reference for the further research on Chaihu Guizhi Ganjiangtang in the treatment of dyspepsia caused by CC.

[摘 要] 目的：探讨DNA甲基转移酶1（DNMT1）通过稳定zeste基因增强子同源物2（EZH2）促进结直肠癌（CRC）HCT8细胞增殖与迁移的机制。方法：利用生物信息学方法分析DNMT1在CRC组织中的表达水平。WB法检测DNMT1在CRC细胞HCT8、SW620和正常结肠上皮细胞NCM460中的表达。通过siRNA或慢病毒载体转染HCT8细胞，分为siNC组、siDNMT1组、Vector组、DNMT1-OE组、siTRAF6组、siEZH2组、siEZH2 + DNMT1-OE组。采用克隆形成实验、CCK-8法、Transwell实验和划痕愈合实验检测敲低或过表达DNMT1对HCT8细胞增殖与迁移的影响，WB和qPCR法检测EZH2蛋白和mRNA水平，免疫沉淀（IP）法检测EZH2泛素化水平，免疫荧光双染检测肿瘤坏死因子受体相关因子6（TRAF6）与EZH2的细胞内共定位情况，克隆形成和划痕愈合实验验证EZH2对DNMT1功能的逆转作用。收集2022—2025年间郑州大学附属洛阳中心医院手术切除的12例CRC患者的癌及癌旁组织标本，采用免疫组化法检测CRC组织中DNMT1、TRAF6和EZH2的表达水平。结果：DNMT1在CRC组织中表达显著高于癌旁组织（P < 0.01），且在CRC细胞中表达上调（P < 0.05）；DNMT1敲低显著抑制HCT8细胞增殖及迁移（均P < 0.01），过表达则相反（均P < 0.01）。DNMT1正向调控EZH2的蛋白水平（P < 0.01），而mRNA水平不变（P > 0.05）。MG132可恢复siDNMT1组的EZH2蛋白表达（P < 0.01），且siDNMT1组EZH2泛素化水平升高。DNMT1负向调控TRAF6的表达（P < 0.01），且TRAF6与EZH2在细胞质中共定位，IP证实两者直接结合。敲低TRAF6可减弱EZH2的泛素化水平，敲低EZH2可逆转DNMT1对HCT8细胞增殖、迁移的促进作用（均P < 0.01）。DNMT1和EZH2在CRC组织中呈高表达（P < 0.01），TRAF6在CRC组织中表达显著低于癌旁组织（P < 0.05）。结论：DNMT1通过抑制TRAF6稳定EZH2促进CRC细胞的增殖和迁移，DNMT1、TRAF6和EZH2可能是CRC治疗的潜在靶点。

OBJECTIVE To investigate the effects of baicalin （BC） on insulin resistance in rats with gestational diabetes mellitus （GDM） and its underlying mechanism based on the adenosine monophosphate-activated protein kinase （AMPK）/suppressor of variegation 3-9 homolog 1 （SUV39H1）/histone H3 lysine 9 trimethylation （H3K9me3） axis. METHODS A GDM rat model was established by a combination of a high-fat diet and streptozotocin injection. The successfully modeled rats were divided into the GDM group， BC low-dose group， BC high-dose group， and high-dose of BC+AMPK inhibitor （Compound C） group， with 10 rats in each group. Another 10 pregnant rats fed a normal diet served as the control group. Rats in each group were given corresponding drugs/normal saline intragastrically and/or intraperitoneally， once daily for 2 consecutive weeks. After the last administration， the levels of fasting blood glucose （FBG）， pancreatic function indexes [fasting insulin （FINS）， homeostasis model assessment of insulin resistance （HOMA-IR）， insulin sensitivity index （ISI）]， blood lipid indexes （total cholesterol， triglyceride， low-density lipoprotein cholesterol）， liver function indexes （alanine transferase， aspartate transferase， alkaline phosphatase）， inflammatory indicators （C-reactive protein， interleukin-1β， interleukin-6）， metabolic regulatory protein [complement-C1q/tumor necrosis factor-related protein 3 （CTRP3）]， insulin sensitivity related factors [glucose transporter 4 （GLUT4）， adiponectin]， and oxidative stress indicators [superoxide dismutase （SOD）， catalase （CAT）， malondialdehyde （MDA）] were measured. Pathological changes in liver tissue were observed， and the expressions of proteins related to the AMPK/SUV39H1/H3K9me3 axis in liver tissue were detected. RESULTS Compared with the GDM group， rats in the BC low- and high-dose groups showed varying degrees of improvement in pathological changes such as disordered cell arrangement， vacuolar degeneration， lipid deposition， and inflammatory cell infiltration in liver tissue. Their FBG and FINS levels， HOMA-IR， the levels of blood lipid indexes， liver function indexes， inflammatory indicators and MDA， and the expressions of SUV39H1 and H3K9me3 were significantly decreased or down-regulated， while metabolic regulatory protein， insulin sensitivity-related factors and AMPK protein phosphorylation levels were significantly increased （ P ＜0.05）. The improvement was more significant in the BC high-dose group （ P ＜0.05）. Compound C could significantly reverse the ameliorative effects of high-dose BC on the above quantitative indicators （ P ＜0.05）. CONCLUSIONS BC can significantly reduce oxidative stress and inflammatory responses， increase serum levels of CTRP3， GLUT4 and adiponectin， thereby improving insulin resistance in GDM rats. These effects may be related to the activation of AMPK and inhibition of SUV39H1-mediated H3K9me3 modification.

Abnormal activation of the Janus kinase/signal transducer and activator of transcription （JAK/STAT） signaling pathway is involved in the pathogenesis of diffuse large B-cell lymphoma （DLBCL）. In recent years， inhibitors targeting JAK2 and STAT3 have emerged as promising therapeutic candidates in DLBCL. This review summarizes the efficacy and safety profiles of JAK2 inhibitors （e.g.， ruxolitinib） and STAT3 inhibitors （direct small-molecule inhibitors， the antisense oligonucleotide， and proteolysis targeting chimeras， etc.） in preclinical models and clinical trials. Accumulating evidence indicates that JAK2 and STAT3 inhibitors exhibit antitumor activity and are generally well tolerated in a subset of DLBCL patients. Meanwhile， the development of novel drug delivery systems has significantly enhanced the stability， bioavailability， and targeting ability of the compounds. Furthermore， JAK2 and STAT3 inhibitors may exhibit synergistic effects when combined with other therapy strategies （such as combinations with B-cell receptor signaling pathway inhibitors， immunomodulators， or other targeted drugs）. However， current clinical applications are still in their early stages. Future research should concentrate on precision treatment strategies based on the genetic subtyping of DLBCL， and further refine the delivery systems for inhibitors as well as combination drug regimens to improve clinical outcomes.

ObjectiveTo establish a mouse model of particulate matter 2.5 （PM_2.5）-induced dry eye and investigate whether Chufeng Yisuntang can ameliorate the PM_2.5-induced ocular surface damage by regulating the reactive oxygen species （ROS）/p38 mitogen-activated protein kinase （p38 MAPK） signaling pathway. MethodsSixty 8-week-old male C57BL/6J mice were used. Ten were randomly selected as the control group. The remaining 50 mice received topical instillation of 1 drop （0.1 mL） of 5 g·L^-1 PM_2.5 suspension in both eyes， four times daily. Successfully modeled mice were randomized into four groups （n=10）： Model， p38 MAPK inhibitor， Chufeng Yisuntang， and combination （Chufeng Yisuntang at 7.3 g·kg^-1 + p38 MAPK inhibitor SB203580 at 5 mg·kg^-1）. Chufeng Yisuntang was administered via gavage， and the inhibitor group via intraperitoneal injection. The control and model groups received equal volumes of distilled water by gavage. All treatments lasted for 4 weeks. General conditions were dynamically observed. Tear secretion， tear film break-up time， and corneal fluorescein staining were assessed. After intervention for 4 weeks， hematoxylin and eosin （HE） staining was used to examine the histopathological changes. Enzyme-linked immunosorbent assay （ELISA） was adopted to measure serum levels of ROS， malondialdehyde （MDA）， superoxide dismutase （SOD） 1， and SOD2. Western blot and Real-time PCR were employed to determine the protein and gene levels， respectively， of p38 MAPK， B-cell lymphoma-2 （Bcl-2）， Bcl-2-associated X protein （Bax）， and cysteinyl aspartate-specific proteinase-3 （Caspase-3） in the corneal tissue. ResultsCompared with the control group， the model group exhibited reduced tear secretion volume and tear film breakup time， along with increased corneal fluorescein staining scores （P<0.01）. Compared with the model group， the Chufeng Yisuntang group， p38 MAPK inhibitor group， and combination group demonstrated increased tear secretion volume and tear film breakup time， along with decreased corneal fluorescein staining scores （P<0.01）. HE staining revealed that compared with the control group， the model group exhibited marked increases in corneal epithelial cell layers and epithelial thickness， along with reduced meibomian gland acini and intensely stained， densely packed nuclei around the acini. Compared with the model group， the Chufeng Yisuntang group， p38 MAPK inhibitor group， and combination group showed intact corneal structure， improved cell morphology， and reduced damage severity. ELISA revealed elevated ROS and MDA levels （P<0.01） and decreased SOD1 and SOD2 levels （P<0.01） in the model group compared with the control group. Compared with the model group， Chufeng Yisuntang， p38 MAPK inhibitor， and the combination lowered ROS and MDA levels （P<0.01）， while raising SOD1 and SOD2 levels （P<0.05， P<0.01）. Western blot revealed that compared with the control group， the model group exhibited increased protein levels of p38 MAPK， Bax， and Caspase-3 （P<0.01） and reduced protein level of Bcl-2 （P<0.01）. Compared with the model group， Chufeng Yisuntang， p38 MAPK inhibitor， and the combination down-regulated the protein levels of p38 MAPK， Bax， and Caspase-3 （P<0.01）， while up-regulating the protein level of Bcl-2 （P<0.01）. Compared with the Chufeng Yisuntang group， the combination group exhibited decreased protein levels of p38 MAPK， Bax， and Caspase-3 （P<0.01） and increased protein level of Bcl-2 （P<0.01）. Real-time PCR revealed that compared with the control group， the model group exhibited upregulated mRNA levels of p38 MAPK， Bax， and Caspase-3 （P<0.01）， and downregulated mRNA level of Bcl-2 （P<0.01）. Compared with the model group， Chufeng Yisuntang， p38 MAPK inhibitor， and the combination down-regulated the mRNA levels of p38 MAPK， Bax， and Caspase-3 （P<0.01）， while up-regulating the mRNA level of Bcl-2 （P<0.05， P<0.01）. Compared with the Chufeng Yisuntang group， the combination group exhibited decreased mRNA levels of p38 MAPK， Bax， and Caspase-3 expression （P<0.05， P<0.01） and increased mRNA level of Bcl-2 （P<0.01）. ConclusionChufeng Yisuntang may partially protect against PM_2.5-induced corneal injury by inhibiting the ROS/p38 MAPK pathway， enhancing antioxidant defense， and reducing epithelial apoptosis.

OBJECTIVE To investigate the effects and potential mechanism of Qiangxin decoction on mitochondrion of rats with chronic heart failure （CHF）. METHODS The CHF model was established by ligating the left anterior descending branch of the coronary artery. Modeled rats were divided into model group， Qiangxin decoction low-dose and high-dose groups （12.25， 24.50 g/kg， calculated by crude drug）， and chemical medicine group （Sacubitril valsartan sodium tablets， 10.42 mg/kg）， with 10 rats in each group； control group was set up without treatment. Each group of rats was orally administered with the corresponding medication or normal saline twice a day for 28 consecutive days. After the last medication， the contents of N-terminal pro-brain natriuretic peptide （NT-proBNP） and adenosine triphosphate （ATP） in serum and phosphatidic acid （PA） and cardiolipin （CL） in myocardial tissue were all detected； the pathological damage and collagen fibrosis of rat myocardial tissue were observed； the apoptosis of myocardial cells was determined； the ultrastructure of myocardial tissue was observed； the protein expressions of mitofusin 1 （Mfn1）， Mfn2， optic atrophy protein 1 （OPA1） and dynamin-related protein 1 （Drp1） were all detected in myocardial tissue. RESULTS Compared with control group，the serum content of NT-proBNP， apoptotic rate of myocardial cells， and relative expressions of S-OPA1 and Drp1 proteins were all increased significantly； serum content of ATP，contents of PA and CL， and relative expressions of Mfn1， Mfn2 and L-OPA1 proteins were all significantly reduced （P＜0.05）. There were abnormal membrane tissue structure in various layers of myocardial tissue， degeneration and necrosis of myocardial cells， and severe fibrosis； the mitochondria were swollen， with reduced or absent cristae， and uneven matrix density. After intervention with Qiangxin decoction， the levels of the aforementioned quantitative indicators in serum and myocardial tissue of rats （excluding CL content in the Qiangxin decoction low- dose group） were significantly reversed （P＜0.05）； the pathological damage of myocardial tissue had significantly improved， fibrosis had significantly reduced， mitochondrial morphology tended to be normal， cristae had increased， and matrix density was uniform. CONCLUSIONS Qiangxin decoction can regulate myocardial mitochondrial function and structural integrity of CHF rats， thereby improving myocardial energy metabolism and antagonizing myocardial fibrosis， the mechanism of which may be associated with activating PA/Mfn/CL signaling pathway.

OBJECTIVE To investigate the effects and potential mechanism of Qiangxin decoction on mitochondrion of rats with chronic heart failure （CHF）. METHODS The CHF model was established by ligating the left anterior descending branch of the coronary artery. Modeled rats were divided into model group， Qiangxin decoction low-dose and high-dose groups （12.25， 24.50 g/kg， calculated by crude drug）， and chemical medicine group （Sacubitril valsartan sodium tablets， 10.42 mg/kg）， with 10 rats in each group； control group was set up without treatment. Each group of rats was orally administered with the corresponding medication or normal saline twice a day for 28 consecutive days. After the last medication， the contents of N-terminal pro-brain natriuretic peptide （NT-proBNP） and adenosine triphosphate （ATP） in serum and phosphatidic acid （PA） and cardiolipin （CL） in myocardial tissue were all detected； the pathological damage and collagen fibrosis of rat myocardial tissue were observed； the apoptosis of myocardial cells was determined； the ultrastructure of myocardial tissue was observed； the protein expressions of mitofusin 1 （Mfn1）， Mfn2， optic atrophy protein 1 （OPA1） and dynamin-related protein 1 （Drp1） were all detected in myocardial tissue. RESULTS Compared with control group，the serum content of NT-proBNP， apoptotic rate of myocardial cells， and relative expressions of S-OPA1 and Drp1 proteins were all increased significantly； serum content of ATP，contents of PA and CL， and relative expressions of Mfn1， Mfn2 and L-OPA1 proteins were all significantly reduced （P＜0.05）. There were abnormal membrane tissue structure in various layers of myocardial tissue， degeneration and necrosis of myocardial cells， and severe fibrosis； the mitochondria were swollen， with reduced or absent cristae， and uneven matrix density. After intervention with Qiangxin decoction， the levels of the aforementioned quantitative indicators in serum and myocardial tissue of rats （excluding CL content in the Qiangxin decoction low- dose group） were significantly reversed （P＜0.05）； the pathological damage of myocardial tissue had significantly improved， fibrosis had significantly reduced， mitochondrial morphology tended to be normal， cristae had increased， and matrix density was uniform. CONCLUSIONS Qiangxin decoction can regulate myocardial mitochondrial function and structural integrity of CHF rats， thereby improving myocardial energy metabolism and antagonizing myocardial fibrosis， the mechanism of which may be associated with activating PA/Mfn/CL signaling pathway.