Activation of glutamatergic neurons in the somatosensory cortex promotes remyelination in ischemic vascular dementia.

Chronic cerebral hypoperfusion can cause progressive demyelination as well as ischemic vascular dementia, however no effective treatments are available. Here, based on magnetic resonance imaging studies of patients with white matter damage, we found that this damage is associated with disorganized cortical structure. In a mouse model, optogenetic activation of glutamatergic neurons in the somatosensory cortex significantly promoted oligodendrocyte progenitor cell (OPC) proliferation, remyelination in the corpus callosum, and recovery of cognitive ability after cerebral hypoperfusion. The therapeutic effect of such stimulation was restricted to the upper layers of the cortex, but also spanned a wide time window after ischemia. Mechanistically, enhancement of glutamatergic neuron-OPC functional synaptic connections is required to achieve the protection effect of activating cortical glutamatergic neurons. Additionally, skin stroking, an easier method to translate into clinical practice, activated the somatosensory cortex, thereby promoting OPC proliferation, remyelination and cognitive recovery following cerebral hypoperfusion. In summary, we demonstrated that activating glutamatergic neurons in the somatosensory cortex promotes the proliferation of OPCs and remyelination to recover cognitive function after chronic cerebral hypoperfusion. It should be noted that this activation may provide new approaches for treating ischemic vascular dementia via the precise regulation of glutamatergic neuron-OPC circuits.

Identification of the mitochondrial protein ADCK2 as a therapeutic oncotarget of NSCLC.

The aarF domain containing kinase 2 (ADCK2) is a mitochondria-locating protein, important for fatty acid metabolism and coenzyme Q biosynthesis. The bioinformatics results show that elevated ADCK2 transcripts in NSCLC correlate with poor overall survival and poor anti-PD-1/PD-L1 therapy response. ADCK2 is overexpressed in local human NSCLC tissues and various primary and established NSCLC cells. In NSCLC cells, ADCK2 shRNA or CRISPR/Cas9 knockout remarkably suppressed cell viability, proliferation, cell cycle progression, cell mobility, and provoked cell apoptosis. Moreover, ADCK2 depletion disrupted mitochondrial functions in NSCLC cells, causing cytochrome C release, mitochondrial depolarization, DNA damage and ATP reduction. Contrarily, ectopic ADCK2 overexpression promoted NSCLC cell growth. Further studies revealed that ADCK2 depletion inactivated Akt-mTOR signaling in primary NSCLC cells. NSCLC xenograft growth in nude mice was significantly hindered after ADCK2 silencing or knockout. ADCK2 depletion, apoptosis induction and oxidative injury as well as ATP reduction and Akt-mTOR inactivation were detected in ADCK2-silenced or ADCK2-knockout NSCLC xenograft tissues. Together overexpressed ADCK2 is important for the growth of NSCLC cells, representing an important therapeutic molecular oncotarget.

The food preservative sodium propionate induces hyperglycaemic state and neurological disorder in zebrafish.

Propionate is an effective mould inhibitor widely used as a food preservative. In this study, we used zebrafish to explore the adverse effects of long-term exposure to low concentrations of sodium propionate and the underlying molecular mechanisms (from larvae to adult). When exposed for 3 months, we found that blood glucose, total cholesterol, and triglyceride levels increased, and zebrafish developed a hyperglycaemic state. New tank test results showed depression in zebrafish reduced 5-hydroxytryptamine levels in the brain and damaged the dopamine system. At the same time, the results of the color preference test showed that zebrafish had cognitive impairments. In addition, Hypothalamic-Pituitary-Adrenal axis analysis revealed abnormal gene expression, increased cortisol levels, and reduced glucocorticoid receptor mRNA levels, which were consistent with depressive behavior. We also observed abnormal transcription of inflammatory and apoptotic factors. Overall, we found that chronic exposure to sodium propionate induces depressive symptoms. This may be related to the activation of the HPA axis by the hyperglycaemic state, thereby inducing inflammation and disrupting the dopaminergic system. In summary, this study provides theoretical and technical support for the overlap of the emotional pathogenesis associated with diabetes.

Visible-light photocatalytic radical addition-translocation-cyclization to construct sulfonyl-containing azacycles.

Herein, a novel visible-light photocatalytic radical addition-translocation-cyclization (RATC) approach for the efficient synthesis of sulfonyl-containing azacycles is described. The reaction delivers a wide range of monocyclic, bicyclic and polycyclic azacycles by using easily prepared sodium sulfinates and N-homopropargylic amines as starting materials. Instead of the traditionally used toxic tin reagents and thermally hazardous azos in the RATC process, clean, renewable and sustainable visible light combined with a catalytic amount of photosensitizer is used in this process. Moreover, the successful transformation of some drug derivatives further highlights the potential application of this procedure.

Exposure of zebrafish embryos to sodium propionate disrupts circadian behavior and glucose metabolism-related development.

Sodium propionate is widely used as a preservative in food. The widespread use of preservatives is known to cause both environmental and public health problems. This study aimed to investigate the effects of sodium propionate on the developmental behavior and glucose metabolism of zebrafish. Our results showed that sodium propionate had no significant effect on the embryonic morphological development of zebrafish embryos but changed the head eye area. Then we found sodium propionate disturbed the thigmotaxis behavior, impaired neural development. Moreover, changes in clock gene expression disrupted the circadian rhythm of zebrafish. Circadian genes regulated insulin sensitivity and secretion in various tissues. Then our results showed that the disorder of circadian rhythm in zebrafish affected glucose metabolism and insulin resistance, which damaged the development of retina. Therefore, the safety of propionate should be further evaluated.

Ruthenium(II)-Catalyzed Chelation-Assisted Desulfitative Arylation of Benzo[h]quinolines with Arylsulfonyl Chlorides.

Herein, a novel chelation-assisted C-H arylation reaction of benzo[h]quinoline is described. This transformation, using [RuCl2(p-cymene)]2 as the catalyst and cheap and easily accessible arylsulfonyl chlorides as the arylation source, featured simple reaction conditions, a broad substrate scope, and functional group tolerance. The successful application of some bioactive-molecule-based sulfonyl chlorides further highlighted the potential utility and importance of this desulfitative C-H arylation protocol.

Triptolide protects against white matter injury induced by chronic cerebral hypoperfusion in mice.

White matter injury is the major pathological alteration of subcortical ischemic vascular dementia (SIVD) caused by chronic cerebral hypoperfusion. It is characterized by progressive demyelination, apoptosis of oligodendrocytes and microglial activation, which leads to impairment of cognitive function. Triptolide exhibits a variety of pharmacological activities including anti-inflammation, immunosuppression and antitumor, etc. In this study, we investigated the effects of triptolide on white matter injury and cognitive impairments in mice with chronic cerebral hypoperfusion induced by the right unilateral common carotid artery occlusion (rUCCAO). We showed that triptolide administration alleviated the demyelination, axonal injury, and oligodendrocyte loss in the mice. Triptolide also improved cognitive function in novel object recognition test and Morris water maze test. In primary oligodendrocytes following oxygen-glucose deprivation (OGD), application of triptolide (0.001-0.1 nM) exerted concentration-dependent protection. We revealed that the protective effect of triptolide resulted from its inhibition of oligodendrocyte apoptosis via increasing the phosphorylation of the Src/Akt/GSK3ß pathway. Moreover, triptolide suppressed microglial activation and proinflammatory cytokines expression after chronic cerebral hypoperfusion in mice and in BV2 microglial cells following OGD, which also contributing to its alleviation of white matter injury. Importantly, mice received triptolide at the dose of 20 µg·kg-1·d-1 did not show hepatotoxicity and nephrotoxicity even after chronic treatment. Thus, our results highlight that triptolide alleviates whiter matter injury induced by chronic cerebral hypoperfusion through direct protection against oligodendrocyte apoptosis and indirect protection by inhibition of microglial inflammation. Triptolide may have novel indication in clinic such as the treatment of chronic cerebral hypoperfusion-induced SIVD.

[Spatial variability of soil properties in fixed sand dunes of the Eastern Ningxia Province]. / 宁夏东部风沙区固定沙丘土壤性质小尺度空间变异特征.

As sand dunes gradually become fixed, soil particle size, soil organic carbon (SOC) and total nitrogen (TN) contents vary across different locations of the dunes. To investigate the spatial variation of soil particle size distribution and soil nutrition in the fixed sand dunes, we examined particle composition, SOC and TC features in different locations of dunes in the Eastern Ningxia. The results showed that the particle sizes of each soil layer were mainly characterized by medium and coarse sands. The SOC and TN contents were higher in surface soil layers, with a maximum of 5.781 and 0.412 g·kg-1, respectively, which were observed in interdune lands and dune ridges, while the leeward slope of the dunes showed the least. The SOC content of both the leeward and windward slope gradually decreased with increasing soil depth along the dune. By contrast, that of the interdune lands decreased first and then increased. At small scale, both the SOC and TN contents showed a clear spatial heterogeneity. There was a positive correlation between soil nutrition contents (SOC and TN) and silt and very fine sand contents in the fixed sand dunes, and a negative correlation with medium and coarse sand contents. Our results implied that soil particle size composition influenced SOC and TN contents. The contents of soil nutrition increased with increa-sing contribution of fine particles, highlighting the role of fine particles in adhesion and accumulation of organic matter.

LMNB2 promotes the progression of colorectal cancer by silencing p21 expression.

Colorectal cancer is the second common cause of death worldwide. Lamin B2 (LMNB2) is involved in chromatin remodeling and the rupture and reorganization of nuclear membrane during mitosis, which is necessary for eukaryotic cell proliferation. However, the role of LMNB2 in colorectal cancer (CRC) is poorly understood. This study explored the biological functions of LMNB2 in the progression of colorectal cancer and explored the possible molecular mechanisms. We found that LMNB2 was significantly upregulated in primary colorectal cancer tissues and cell lines, compared with paired non-cancerous tissues and normal colorectal epithelium. The high expression of LMNB2 in colorectal cancer tissues is significantly related to the clinicopathological characteristics of the patients and the shorter overall and disease-free cumulative survival. Functional analysis, including CCK8 cell proliferation test, EdU proliferation test, colony formation analysis, nude mouse xenograft, cell cycle, and apoptosis analysis showed that LMNB2 significantly promotes cell proliferation by promoting cell cycle progression in vivo and in vitro. In addition, gene set enrichment analysis, luciferase report analysis, and CHIP analysis showed that LMNB2 promotes cell proliferation by regulating the p21 promoter, whereas LMNB2 has no effect on cell apoptosis. In summary, these findings not only indicate that LMNB2 promotes the proliferation of colorectal cancer by regulating p21-mediated cell cycle progression, but also suggest the potential value of LMNB2 as a clinical prognostic marker and molecular therapy target.

The Relationship Between ß-cell Function Indices and Sudomotor Function in Chinese Patients with Type 2 Diabetes.

PURPOSE: SUDOSCAN, a new non-invasive, quick, sensitive and quantitative technique, has been developed to detect diabetic peripheral neuropathy, and the latter is believed to be correlated with impaired ß-cell function. The purpose of the present study was to investigate the associations between ß-cell function indices and sudomotor function in Chinese type 2 diabetes. METHODS: A total of 266 Chinese patients with type 2 diabetes were enrolled. Sudomotor function was assessed using electrochemical skin conductance of hands and feet. Pancreatic ß-cell function was determined by homeostasis model assessment of ß-cell function index, early-phase ß-cell function indices and total ß-cell function indices. Pearson correlation analysis and multiple linear stepwise regression analysis were carried out to explore the associations between ß-cell function indices and sudomotor function. RESULTS: Patients with lower early-phase ß-cell function had lower electrochemical skin conductance levels of hands and feet and higher asymmetry ratio of hands and feet. Both Pearson correlation analysis and multiple linear stepwise regression analysis showed significantly positive relationships between early-phase ß-cell function and electrochemical skin conductance levels of hands and feet, after controlling for potential confounders (P<0.05). CONCLUSIONS: Impaired early-phase ß-cell function was positively associated with sudomotor dysfunction in Chinese patients with type 2 diabetes. We speculated that impaired early-phase ß-cell function may be associated with the incidence of sudomotor dysfunction in patients with T2DM.

Enhancing the bioconversion of phytosterols to steroidal intermediates by the deficiency of kasB in the cell wall synthesis of Mycobacterium neoaurum.

BACKGROUND: The bioconversion of phytosterols into high value-added steroidal intermediates, including the 9α-hydroxy-4-androstene-3,17-dione (9-OHAD) and 22-hydroxy-23,24-bisnorchol-4-ene-3-one (4-HBC), is the cornerstone in steroid pharmaceutical industry. However, the low transportation efficiency of hydrophobic substrates into mycobacterial cells severely limits the transformation. In this study, a robust and stable modification of the cell wall in M. neoaurum strain strikingly enhanced the cell permeability for the high production of steroids. RESULTS: The deletion of the nonessential kasB, encoding a ß-ketoacyl-acyl carrier protein synthase, led to a disturbed proportion of mycolic acids (MAs), which is one of the most important components in the cell wall of Mycobacterium neoaurum ATCC 25795. The determination of cell permeability displayed about two times improvement in the kasB-deficient strain than that of the wild type M. neoaurum. Thus, the deficiency of kasB in the 9-OHAD-producing strain resulted in a significant increase of 137.7% in the yield of 9α-hydroxy-4-androstene-3,17-dione (9-OHAD). Ultimately, the 9-OHAD productivity in an industrial used resting cell system was reached 0.1135 g/L/h (10.9 g/L 9-OHAD from 20 g/L phytosterol) and the conversion time was shortened by 33%. In addition, a similar self-enhancement effect (34.5%) was realized in the 22-hydroxy-23,24-bisnorchol-4-ene-3-one (4-HBC) producing strain. CONCLUSIONS: The modification of kasB resulted in a meaningful change in the cell wall mycolic acids. Deletion of the kasB gene remarkably improved the cell permeability, leading to a self-enhancement of the steroidal intermediate conversion. The results showed a high efficiency and feasibility of this construction strategy.

New azaphilones, phomopsones A-C with biological activities from an endophytic fungus Phomopsis sp. CGMCC No.5416.

Three undescribed azaphilones, phomopsones A-C (1-3) and two known azaphilones (4-5) were isolated from the culture of endophytic fungus Phomopsis sp. CGMCC No.5416 from the stems of Achyranthes bidentata. Their structures were determined by spectroscopic analysis (HRESIMS, 1D and 2D NMR), and the absolute configurations were determined by CD spectroscopy. Compounds 2 and 3 showed significant inhibitory activities against HIV-1 with against HIV-1 with IC50 values of 7.6 and 0.5 µmol/L, respectively. Compounds 2 and 3 also displayed moderate cytotoxicity with CC50 values of 3.2-303 µmol/L against A549, MDA-MB-231 and PANC-1 cell lines. Moreover, compound 3 can induce the early apoptosis of PANC-1 cancer cells with the apoptosis rate of 28.54%.

Relationship between ß-amyloid protein 1-42, thyroid hormone levels and the risk of cognitive impairment after ischemic stroke.

BACKGROUND: Post-stroke cognitive impairment (PSCI) is not only a common consequence of stroke but also an important factor for adverse prognosis of patients. Biochemical indicators such as blood lipids and blood pressure are affected by many factors, and the ability of evaluating the progress of patients with PSCI is insufficient. Therefore, it is necessary to find sensitive markers for predicting the progress of patients and avoiding PSCI. Recent studies have shown that ß-amyloid protein 1-42 (Aß1-42) and thyroid hormone levels are closely related to PSCI, which may be the influencing factors of PSCI, but there are few related studies. AIM: To investigate the relationship between serum levels of Aß and thyroid hormones in acute stage and PSCI and its predicted value. METHODS: A total of 195 patients with acute cerebral infarction confirmed from June 2016 to January 2018 were enrolled in this study. Baseline data and serological indicators were recorded to assess cognitive function of patients. All patients were followed up for 1 year. Their cognitive functions were evaluated within 1 wk, 3 mo, 6 mo and 1 yr after stroke. At the end of follow-up, the patients were divided into PSCI and non-PSCI according to Montreal cognitive assessment score, and the relationship between biochemical indexes and the progression of PSCI was explored. RESULTS: Compared with patients with non-PSCI, the levels of Aß1-42, triiodothyronine (T3) and free thyroxin were lower in the patients with PSCI. Repeated measures analysis of variance showed that the overall content of Aß1-42 and T3 in PSCI was also lower than that of the non-PSCI patients. Further analysis revealed that Aß1-42 (r = 0.348), T3 (r = 0.273) and free thyroxin (r = 0.214) were positively correlated with disease progression (P < 0.05), suggesting that these indicators have the potential to predict disease progression and outcome. Cox regression analysis showed that Aß1-42 and T3 were important factors of PSCI. Then stratified analysis showed that the lower the Aß1-42 and T3, the higher risk of PSCI in patients who were aged over 70, female and illiterate. CONCLUSION: Aß1-42 and T3 have the ability to predict the progression of PSCI, which is expected to be applied clinically to reduce the incidence of PSCI and improve the quality of life of patients.

[Chemistry research on natural product derivatives of dihydro-ß-agarofuran sesquiterpenoids].

Dihydro-ß-agarofuran sesquiterpenoids possess chemical diversity and biodiversity. A dihydro-ß-agarofuran sesquiterpenoid with only hydroxyl groups has been prepared by basic hydrolysis of crude extract of Euonymus bungeanus with 0.4% yield. Twelve derivatives were available in esterification, oxidation, decarboxylation, etc. Extensive ~1H-NMR,~(13)C-NMR, MS spectroscopic analyses and single-crystal X-ray diffraction analysis with Cu Kα radiation indicated that eleven derivatives were new compounds. The results will provide reference for chemistry study on natural product derivatives of dihydro-ß-agarofuran sesquiterpenoids.

Prognostic value of pretreatment albumin to bilirubin ratio in patients with hepatocellular cancer: A meta-analysis.

BACKGROUND: Hepatic function is closely associated with prognosis in patients with hepatocellular cancer (HCC). In this study, a meta-analysis of the published studies was performed to assess the prognostic value of ALBI grade in HCC patients. METHODS: Databases, including PubMed, EMbase, Web of Science, and Cochrane Library were retrieved up to August 2018. The primary outcome was OS and secondary outcome was DFS, the prognostic impact of which was assessed by using hazard ratio (HRs) with corresponding 95% confidence intervals (CIs). The enrolled studies were analyzed by using STATA version 12.0 software. RESULTS: A total of 22,911 patients with HCC in 32 studies were included. Our results demonstrated that high pretreatment ALBI is associated with poor OS (HR = 1.719, 95%CI: 1.666-1.771, P = .000, univariate results; HR = 1.602, 95%CI: 1.470-1.735, P = .000, multivariate results) and poor DFS (HR = 1.411, 95%CI: 1.262-1.561, P = .000, univariate results; HR = 1.264, 95%CI: 1.042-1.485, P = .000, multivariate results). Meanwhile, when the analysis was stratified into subgroups, such as treatment methods, sample size, geographic area, and ALBI grade, the significant correlation in ALBI and poor long-term survival was not altered. CONCLUSION: High pretreatment ALBI is closely associated with poor prognosis in HCC, and High ALBI should be treated as an ideal predictor during hepatocellular therapy.

Identification of flavonoids in Dendrobium huoshanense and comparison with those in allied species of Dendrobium by TLC, HPLC and HPLC coupled with electrospray ionization multi-stage tandem MS analyses.

Dendrobium huoshanense, a unique species in the genus Orchidaceae, is only found in China and is known as "mihu". Due to the lack of quality control, the use of D. huoshanense in the herbal market has been limited. In this study, methods based on thin-layer chromatography, high-performance liquid chromatography and high-performance liquid chromatography coupled with electrospray ionization multi-stage tandem mass spectrometry were used to identify the flavonoids in D. huoshanense and distinguish this species from other Dendrobium species. Using thin-layer chromatography, a characteristic band was observed for D. huoshanense, and this band was absent from the thin-layer chromatography plates of other Dendrobium species. Then, using high-performance liquid chromatography, nine peaks of flavonoids were observed in the chromatograms of ten batches of D. huoshanense. Ultimately, 22 flavonoids in D. huoshanense were identified by multi-stage tandem mass spectrometry, and 11 of these compounds are being reported from D. huoshanense for the first time. In addition, two compounds both with molecular weights of 710, were identified as being unique to D. huoshanense; one of these compounds, apigenin-6-C-α-L-rhamnosyl-(1→2)-ß-D-glucoside-8-C-α-L-arabinoside, was proven to be responsible for the characteristic thin-layer chromatography band of D. huoshanense. These analysis methods can be applied for the identification and quality control of D. Huoshanense.

Nanomedicine Strategies for Sustained, Controlled and Targeted Treatment of Alzheimer's Disease.

BACKGROUND: Alzheimer's disease (AD) is one of the most devastating diseases worldwide. The current drugs for AD can only ameliorate the symptoms rather than reverse or prevent the progress of AD. On the other hand, blood-brain barrier (BBB), as a natural barrier, significantly impedes drug delivery from the blood circulation into the brain. Nanomedicine can be a safe, effective and promising approach to treat AD. OBJECTIVE: This review summarizes the recent nanomedicine research in this area, including the use of liposomes and nanoparticles (NPs), to provide new approach for targeted treatment of AD. METHOD: Collecting and referring to the related literature in recent 10 years, via searching MeSH Terms "Alzheimer's disease; nanomedicine; nanoparticle; amyloid ß peptide; tau protein; autophagy". RESULTS: Nanomedicines show superiority over conventional anti-AD drugs as a potential weapon against AD by the five proposed mechanisms: many unfavorable pharmaceutical properties of conventional anti-AD drugs maybe greatly overcome by nanomedicine; nanomedicines trigger efficient production of high-titer anti-Aß antibodies following controlled release of antigens by them; some apolipoprotein- based nanomedicines could preferably bind to Aß and increase the elimination of Aß nanomedicine-induced autophagy could be facilitated to increase the elimination of Aß nanomedicineinduced inhibition of tau aggregation. CONCLUSION: Therefore, nanomedicine-mediated drug therapy is promising in the treatment of AD.

[Preparation of a polyclonal antibody against human LYZL4 and its expression in the testis].

OBJECTIVE: To prepare a polyclonal antibody against human lysozyme-like protein 4 (LYZL4) expressed in the prokaryotic system and identify the distribution of LYZL4 in the testis. METHODS: The full-length cDNA of LYZL4 was cloned into the pET32a plasmid and the expression of the recombinant LYZL4 (rLYZL4) was induced by IPTG. The rLYZL4 was purified by Ni-NTA and chitin affinity chromatography respectively and its bactericidal activity was observed by bilayer agar plate diffusion assay. The purified rLYZL4 was used as an immunogen to generate the polyclonal antibody, followed by examination of the antibody titer by ELISA and its specificity by Western blot. The distribution of LYZL4 in human tissue, sperm and seminal plasma was identified and its subcellular localization in the testis was determined by immunohistochemistry. RESULTS: rLYZL4 was expressed efficiently in the prokaryotic system and exhibited no bacteriolytic activity against M. lysodeikticus and E. coli. The anti-rLYZL4 polyclonal antibody could bind the recombinant protein with a high sensitivity and specificity. LYZL4 was identified in the testis, epididymis and sperm protein extracts and localized in the acrosomal region of round and elongating spermatids. CONCLUSIONS: An anti-rLYZL4 polyclonal antibody was successfully prepared using the prokaryotic expression system. LYZL4 was detected in the acrosomal region of round and elongating spermatids, suggesting an association with the structure and function of the acrosome.

Constituents from the Roots of Actinidia chinensis and Their Cytochrome P450 Enzyme Inhibitory Activities.

A newly discovered triterpenoid, (2α,3ß)-2,3,23-trihydroxyurs-13(18)-en-28-oic acid (1), along with twelve known compounds (2 - 13), were isolated from the roots of Actinidia chinensis Planch (Actinidiaceae). Their chemical structures were determined by 1D- and 2D-NMR spectra and mass spectrometry (MS). The crude extracts and six main constituents (8 - 13) were tested for cytochrome P450 (CYPs) enzyme inhibitory activity. The results showed that, except for compound 8, compounds 9 - 13 had different inhibitory effects on the cytochrome P450 (CYPs) enzyme, and compound 9 significantly inhibited the catalytic activities of CYP3A4 to < 10% of its control activities.

[Expression of human lysozyme-like protein 6 in the male reproductive system].

OBJECTIVE: To study the expression of human lysozyme-like protein 6 (LYZL6) in the male reproductive system and its physiological role. METHODS: The recombinant P. pastoris strain was cultured and induced with methanol to express LYZL6, followed by purification using chitin affinity chromatography. The bactericidal activity of the recombinant LYZL6 was observed by bilayer agar plate diffusion assay, and then the recombinant protein was used as an immunogen to generate polyclonal antibodies, whose specificity was examined by ELISA. The distribution of LYZL6 in the human tissue and semen was identified by Western blotting and the subcellular localization in the testis was investigated by immunohistochemistry. RESULTS: At pH 5.6, recombinant LYZL6 exhibited a high bacteriolytic activity against M. lysodeikticus. ELISA analysis showed that the anti-LYZL6 polyclonal antibodies could bind the recombinant protein with a high specificity. Western blot manifested the expression of LYZL6 in the testis and epididymis, higher in the former than in the latter. LYZL6 was also detected in the sperm protein extract, while protein bands were not observed in the seminal plasma. Immunodetection with a specific antiserum localized the LYZL6 protein in the late spermatocytes and round spermatids. CONCLUSIONS: LYZL6 has a higher bacteriolytic activity under low pH condition and is bound to spermatozoa after secreted in the testicular epithelia, suggesting that LYZL6 could act as a potential hydrolase for carbohydrates in zona pellucida penetration.