Integrative Analysis of the Microbiome and Metabolome of Broiler Intestine: Insights into the Mechanisms of Probiotic Action as an Antibiotic Substitute.

Antibiotic substitutes have become a research focus due to restrictions on antibiotic usage. Among the antibiotic substitutes on the market, probiotics have been extensively researched and used. However, the mechanism by which probiotics replace antibiotics remains unclear. In this study, we aimed to investigate this mechanism by comparing the effects of probiotics and antibiotics on broiler growth performance and intestinal microbiota composition. Results shown that both probiotics and antibiotics increased daily weight gain and reduced feed conversion rate in broilers. Analysis of ileum and cecum microorganisms via 16S rRNA gene sequencing revealed that both interventions decreased intestinal microbial diversity. Moreover, the abundance of Bacteroides increased in the mature ileum, while that of Erysipelatoclostridium decreased in the cecum in response to both probiotics and antibiotics. The main metabolites of probiotics and antibiotics in the intestine were found to be organic acids, amino acids, and sugars, which might play comparable roles in growth performance. Furthermore, disaccharides and trisaccharides may be essential components in the ileum that enable probiotics to replace antibiotics. These findings provide important insights into the mechanisms underlying the use of probiotics as antibiotic substitutes in broiler breeding.

Degradation of indole via a two-component indole oxygenase system from Enterococcus hirae GDIAS-5.

Animal farming copiously generates indoles, which contribute to odor and pose a challenge for deodorization. While biodegradation is widely accepted, there is a lack of suitable indole-degrading bacteria for animal husbandry. In this study, we aimed to construct genetically engineered strains with indole-degrading abilities. Enterococcus hirae GDIAS-5 is a highly efficient indole-degrading bacterium, which functions via a monooxygenase YcnE presumably contributes to indole oxidation. However, the efficiency of engineered Escherichia coli expressing YcnE for indole degradation is lower than that of GDIAS-5. To improve its efficacy, the underlying indole-degradation mechanisms in GDIAS-5 were analyzed. An ido operon that responds to a two-component indole oxygenase system was identified. In vitro experiments showed that the reductase component of YcnE, YdgI, can improve the catalytic efficiency. The reconstruction of the two-component system in E. coli exhibited higher indole removal efficiency than GDIAS-5. Furthermore, isatin, the key intermediate metabolite in indole degradation, might be degraded via a novel isatin-acetaminophen-aminophenol pathway involving an amidase whose coding gene is located near the ido operon. The two-component anaerobic oxidation system, upstream degradation pathway, and engineering strains investigated in this study provide important insights into indole degradation metabolism and offer efficient resources for achieving bacterial odor elimination.

Natural history and malignant potential of simple ovarian cysts in postmenopausal women: a systematic review and meta-analysis.

IMPORTANCE: Postmenopausal ovarian masses are not uncommon, and the incidence of ovarian cancer rises sharply after menopause. OBJECTIVE: We conducted a systematic review and meta-analysis to investigate the natural history and malignant potential of postmenopausal simple ovarian cysts. EVIDENCE REVIEW: PubMed, MEDLINE, EMBASE, CENTRAL (Cochrane Central Register of Controlled Trials), ClinicalTrials.gov , and ISRCTN (International Standard Randomized Controlled Trial Number Register) were searched from inception to January 31, 2022. Meta-analyses were conducted using R software. FINDINGS: Twelve cohort studies with 1,672 participants and 1,513 ovarian cysts were included. The rates of simple cysts remaining unchanged (38.90%; 95% CI, 19.79%-59.85%; P < 0.01) or disappearing (34.17%; 95% CI, 19.13%-50.93%; P < 0.01) were the highest during conservative observation. The surgery rate for the simple cyst was 19.04% (95% CI, 8.19%-32.92%; P < 0.01). The malignancy rate (including borderline tumors) was very low, approximately 1/10,000 (95% CI, 0% to 0.23%; P = 0.79). CONCLUSIONS: Simple ovarian cysts in postmenopausal women were most likely to remain unchanged or disappear during follow-up. The malignancy rate was approximately 1 in 10,000. Personal preference is the most common reason for surgery.

Cytoskeletal protein SPTA1 mediating the decrease in erectile function induced by high-fat diet via Hippo signaling pathway.

BACKGROUND: The mechanism of high-fat diet (HFD)-induced decrease in erectile function has not been elucidated, and in previous studies, spectrin alpha, erythrocytic 1 (SPTA1) is a cytoskeletal protein that regulates cellular function, which belongs to a family of proteins that can affect cell and tissue growth and development by regulating YAP, an effector on the Hippo signaling pathway, but its particular role has not been elucidated. OBJECTIVE: To explore the role of SPTA1 in the abnormality of erectile function induced by HFD. METHODS: We analyzed the penile tissues of mice on normal diet and HFD by transcriptomics and screened for differentially expressed genes, further identified closely related target genes in rat penile tissues, and verified target gene expression in in vitro construction of high-glucose (HG)-treated corpus cavernosum endothelial cells (CCECs) and corpus cavernosum smooth muscle cells (CCSMCs) models. The distribution of target genes in various cell populations in penile tissues was retrieved by single-cell sequencing Male Health Atlas database. Moreover, interfering with target genes was further applied to explore the mechanisms involved in erectile function decline. RESULTS: Transcriptomic analysis screened out down-regulated differential gene SPTA1; Western blot and immunohistochemistry results showed that SPTA1 expression significantly decreased in the penile tissues of Sprague-Dawley (SD) rats in the HFD group. Immunofluorescence staining showed a positive expression of CD31 and VWF in CCECs and a positive expression of α-SMA in CCSMCs. The expression level of SPTA1 protein significantly decreased in the HG group of CCECs and CCSMCs. The expression of SPTA1 mRNA significantly decreased in CCSMCs while significantly increased in CCECs. SPTA1 may have various expression patterns and biological functions in different cell populations. Real-time quantitative PCR results showed that the siSPTA1 transfected in CCSMCs had a significant interference effect compared with the control siNC. Transfection of siSPTA1 into CCSMCs resulted in the significant down-regulation of mRNA and protein expression of eNOS, and significant up-regulation of YAP, Caspase-1, GSDMD, GSDMD-N IL-18, and IL-1ß protein expression levels. The expression level of CCSMCs contractile-type protein α-SMA was significantly down-regulated. CONCLUSIONS: The down-regulation of SPTA1 in SD rats fed with HFD may induce cell pyroptosis and lead to the decrease of erectile function by activating the Hippo pathway; these findings may provide new therapeutic targets for improving erectile function.

Neurotoxins and pore forming toxins in sea anemones: Potential candidates for new drug development.

There are two kinds of toxins in sea anemones: neurotoxins and pore forming toxins. As a representative of the sodium channel toxin, the neurotoxin ATX II in neurotoxin mainly affects the process of action potential and the release of transmitter to affect the inactivation of the sodium channel. As the representatives of potassium channel toxins, BgK and ShK mainly affect the potassium channel current. EqTx and Sticholysins are representative of pore forming toxins, which can form specific ion channels in cell membranes and change the concentration of internal and external ions, eventually causing hemolytic effects. Based on the above mechanism, toxins such as ATX II can also cause toxic effects in tissues and organs such as heart, lung and muscle. As an applied aspect it was shown that sea anemone toxins often have strong toxic effects on tumor cells, induce cancer cells to enter the pathway of apoptosis, and can also bind to monoclonal antibodies or directly inhibit relevant channels for the treatment of autoimmune diseases.

Chemoproteomics reveals berberine directly binds to PKM2 to inhibit the progression of colorectal cancer.

Colorectal cancer is one of the most serious tumors and berberine can inhibit the recurrence and transformation of colorectal adenoma into colorectal cancer. However, the direct binding target proteins of berberine in inhibiting colorectal cancer remain unclear. In this study, the chemical proteomics method was used and demonstrated that berberine is directly bound to pyruvate kinase isozyme type M2 (PKM2) in colorectal cancer cells. The triangular N-O-O triangular structure of berberine contributed to hydrophobic interaction with I119 amino acid residues and π-π interaction with F244 amino acid residues of PKM2 protein. Moreover, berberine was shown to inhibit the reprogramming of glucose metabolism and the phosphorylation of STAT3, down regulate the expression of Bcl-2 and Cyclin D1 genes, ultimately inhibiting the progression of colorectal cancer. This study uncovered the direct binding target protein and mechanism of berberine to improve metabolic reprogramming in colorectal cancer, which is helpful to guide the optimization of berberine.

Indole metabolism mechanisms in a new, efficient indole-degrading facultative anaerobe isolate Enterococcus hirae GDIAS-5.

Indole is an inter-species and inter-kingdom signaling molecule widespread in the natural world. A large amount of indole in livestock wastes makes it difficult to be degraded, which causes serious malodor. Identifying efficient and eco-friendly ways to eliminate it is an urgent task for the sustainable development of husbandry. While bioconversion is a widely accepted means, the mechanism of indole microbial degradation is little understood, especially under anaerobic conditions. Herein, a new Enterococcus hirae isolate GDIAS-5, effectively degraded 100 mg/L indole within 28 h aerobically or 5 days anaerobically. Three intermediates (oxindole, isatin, and catechol) were identified in indole degradation, and catechol was further degraded by a meta-cleavage catabolic pathway. Two important processes for GDIAS-5 indole utilization were discovered. One is Fe(III) uptake and reduction, which may be a critical process that is coupled with indole oxidation, and the other is the entire pathway directly involved in indole oxidation and metabolism. Furthermore, monooxygenase ycnE responsible for indole oxidation via the indole-oxindole-isatin pathway was identified for the first time. Bioinformatic analyses showed that ycnE from E. hirae formed a phylogenetically separate branch from monooxygenases of other species. These findings provide new targets and strategies for synthetic biological reconstruction of indole-degrading bacteria.

Tin bisulfide nanoplates anchored onto flower-like bismuth tungstate nanosheets for enhancement in the photocatalytic degradation of organic pollutant.

The development of efficient heterojunctions through a simple and facile method is an effective way to enhance the photocatalytic performance of bismuth-based oxide semiconductors for industrial applications. Here, the novel flower-like type II SnS2/Bi2WO6 heterostructure consisting of bismuth tungstate (Bi2WO6) nanosheets and tin bisulfide (SnS2) nanoplates was successfully designed and synthesized. The crystal structure, composition, morphology, and photoelectric properties of the heterostructure were systematically characterized. In addition, the photocatalytic activity of SnS2/Bi2WO6 was analyzed and compared with Bi2WO6 or SnS2 alone or physical mixture of SnS2 and Bi2WO6. 2%SnS2/Bi2WO6 presents a 3.1 times greater degradation rate constant (0.0065 min-1) than that of Bi2WO6 (0.0021 min-1) under low visible light irradiation (5.3 mW·cm-2, a 44 W LED), while SnS2 alone exhibits no photocatalytic effect toward glyphosate. Furthermore, 2%SnS2/Bi2WO6 maintains 93% of its original photocatalytic activity even after four cycles. The possible photocatalytic degradation pathway of glyphosate and photocatalytic mechanism are also proposed. The excellent photocatalytic performance of SnS2/Bi2WO6 is attributed to the decoration of SnS2 nanoplates on the surface of Bi2WO6, appropriate (113)/(020) ratio, increased visible-light absorption, and effective separation of photoinduced carriers. This paper reports a new methodology that can act as a reference basis to design and develop visible-light responsive photocatalysts with outstanding photocatalytic performance for carbon dioxide reduction, water splitting, and pollutant degradation.

[The Mutated Gene Sequenced by NGS and the Correlation of Their Coexistent Mutual Exclusiveness in NPM1 Mutated Acute Myeloid Leukemia].

OBJECTIVE: To analyze the clinicobiological heterogeneity of NPM1 mutated (NPM1mut) acute myeloid leukemia (AML) detected by next generation sequencing (NGS) and their coexistence and mutual exclusivity relationship in the AML subtype. METHODS: The NGS data based on 112 genes related to blood disease in 238 newly diagnosed patients with NPM1mut were collected. The χ2 test and non-parametric test were used to analyze the distribution correlation between the genes in the mutational spectrum. RESULTS: Among all the patients, at least one co-mutation was detected out. The median number per case of the mutated genes, including NPM1mut was 4.5 (range 2－14), among them, there were 5.0 (range 2－10) for NPM1mut/FLT3-ITD+ and 4.0 (range 2－14) for NPM1mut/FLT3-ITD- cases, but it was no significant difference between the two groups (P=0.378). A total of 240 NPM1 mutational events were detected out in entire 238 NPM1mut patients, of which 10 (4.2%) were missense mutations, and were all found in NPM1mut/FLT3-ITD- patients. Most (9/10, 90%) of these NPM1 missense mutations were accompanied by AML subtype-defining cytogenetic or molecular abnormalities, of which 7 patients were in low risk or 2 in high risk. The most common NPM1mut coexisting mutations were DNMT3A (104, 43.7%), followed were FLT3-ITD (95, 39.9%) and FAT1 (57, 23.9%), FLT3-ITD and DNMT3A showed significant coexistence (P=0.005). FLT3-ITD showed significantly reciprocal exclusivity with FLT3-nonITD (P<0.001), NRAS (P<0.001), PTPN11 (P=0.017) and IDH1 (P=0.005), and showed an exclusivity inclination with KRAS (P=0.073). In addition, FLT3-nonITD along with KRAS (P=0.035), NRAS along with KRAS (P=0.008) and PTPN11 (P=0.039) coexisted significantly. CONCLUSION: Prognoses of AML involving less common NPM1 missense mutations should be stated on a case by case basis. The mutational landscape and co-occurrence and mutual exclusivity correlations of NPM1mut AML provide a mechanism explaining biological diversity and clinical heterogeneity in this AML subset.

Chemoenzymatic access to enantiopure N-containing furfuryl alcohol from chitin-derived N-acetyl-D-glucosamine.

BACKGROUND: Chiral furfuryl alcohols are important precursors for the synthesis of valuable functionalized pyranones such as the rare sugar L-rednose. However, the synthesis of enantiopure chiral biobased furfuryl alcohols remains scarce. In this work, we present a chemoenzymatic route toward enantiopure nitrogen-containing (R)- and (S)-3-acetamido-5-(1-hydroxylethyl)furan (3A5HEF) from chitin-derived N-acetyl-D-glucosamine (NAG). FINDINGS: 3-Acetamido-5-acetylfuran (3A5AF) was obtained from NAG via ionic liquid/boric acid-catalyzed dehydration, in an isolated yield of approximately 31%. Carbonyl reductases from Streptomyces coelicolor (ScCR) and Bacillus sp. ECU0013 (YueD) were found to be good catalysts for asymmetric reduction of 3A5AF. Enantiocomplementary synthesis of (R)- and (S)-3A5HEF was implemented with the yields of up to > 99% and the enantiomeric excess (ee) values of > 99%. Besides, biocatalytic synthesis of (R)-3A5HEF was demonstrated on a preparative scale, with an isolated yield of 65%. CONCLUSIONS: A two-step process toward the chiral furfuryl alcohol was successfully developed by integrating chemical catalysis with enzyme catalysis, with excellent enantioselectivities. This work demonstrates the power of the combination of chemo- and biocatalysis for selective valorization of biobased furans.

Changes in the first postoperative night bispectral index of patients after thyroidectomy with different types of primary anesthetic management: a randomized controlled trial.

Despite major advances in anesthesia management and developments in anesthetic agents, postoperative sleep disturbances remain dissatisfactory for many patients. We hypothesized that propofol might have a subtle influence on sleep after thyroidectomy compared to sevoflurane. A randomized, single-blinded, controlled trial was conducted at the First Hospital of China Medical University from October 2014 to October 2015. One hundred and twenty-four patients undergoing thyroidectomy were enrolled and received sevoflurane (sevoflurane group) or propofol (propofol group) as anesthesia maintenance. Major assessments were made during the operation (different types of anesthetic management) and on the first postoperative night (sleep status). The primary outcome was postoperative sleep status, measured by the BIS-Vista monitor on the first night after surgery between propofol and sevoflurane groups. A total of 105 patients (79 women, 26 men; mean age 49 years; range 18-65 years) were included in the final study sample. All patients in both groups showed one of the five sleep patterns classified by this trial. The BIS-area under the curve was decreased, the sleep efficiency index was significantly increased, and the durations of postoperative sleep and sleep stage N3 were increased by 110.5 and 36.5 min per patient, respectively, in the propofol compared to the sevoflurane group. Propofol might preserve sleep time immediately after thyroidectomy. Clinical Trials.gov identifier: NCT 02146976.

Remote Ischemia Preconditioning Attenuates Blood-Spinal Cord Barrier Breakdown in Rats Undergoing Spinal Cord Ischemia Reperfusion Injury: Associated with Activation and Upregulation of CB1 and CB2 Receptors.

BACKGROUND/AIMS: Remote ischemic preconditioning (RIPC) has protective effects on spinal cord ischemia reperfusion (I/R) injury, but the potential mechanisms remain unclear. In our study, the effects and underlying mechanisms of RIPC on blood-spinal cord barrier (BSCB) breakdown following I/R injury were investigated. METHODS: animals underwent intraperitoneal administration with cannabinoid-1 (CB1) receptor antagonist AM251, cannabinoid-2 (CB2) receptor antagonist AM630 or vehicle 15 minutes before three 3-minute occlusion-reperfusion cycles on the right femoral artery or a sham operation. 30 minutes after the preconditioning, aortic arch was exposed with or without 14-minute occlusion. Neurological function was assessed with Tarlov scoring system. The disruption of BSCB was assessed by measuring Evans Blue (EB) extravasation. The expression of tight junction protein occludin was determined by western blot analyses. The expression and localization of CB1 and CB2 receptors were assessed by western blot and immunofluorescence. RESULTS: RIPC attenuated the motor dysfunction, BSCB disruption and downregulation of occludin after I/R injury, which were impaired by blocking CB1 and CB2 receptors. Moreover, RIPC upregulated the elevated perivascular expression of CB1 and CB2 receptors following I/R injury. CONCLUSIONS: These results indicated that RIPC, through activation and upregulation of CB1 and CB2 receptors, was involved in preserving the integrity of BSCB after spinal cord I/R injury.

Molecular visualizing and quantifying immune-associated peroxynitrite fluxes in phagocytes and mouse inflammation model.

Reactions of peroxynitrite (ONOO-) with biomolecules can lead to cytotoxic and cytoprotective events. Due to the difficulty of directly and unambiguously measuring its levels, most of the beneficial effects associated with ONOO- in vivo remain controversial or poorly characterized. Recently, optical imaging has served as a powerful noninvasive approach to studying ONOO- in living systems. However, ratiometric probes for ONOO- are currently lacking. Herein, we report the design, synthesis, and biological evaluation of F482, a novel fluorescence indicator that relies on ONOO--induced diene oxidation. The remarkable sensitivity, selectivity, and photostability of F482 enabled us to visualize basal ONOO- in immune-stimulated phagocyte cells and quantify its generation in phagosomes by high-throughput flow cytometry analysis. With the aid of in vivo ONOO- imaging in a mouse inflammation model assisted by F482, we envision that F482 will find widespread applications in the study of the ONOO- biology associated with physiological and pathological processes in vitro and in vivo.

Decitabine enhances bortezomib treatment in RPMI 8226 multiple myeloma cells.

The present study investigated the interactions between decitabine (DAC) and bortezomib (BTZ) in RPMI 8226 multiple myeloma (MM) cells. Cells were exposed to DAC alone and in combination with BTZ for 48 h. A Cell Counting Kit­8 assay was performed to assess the rate of proliferation inhibition in the cells. Cell apoptosis was investigated by Annexin V-fluorescein isothiocyanate and propidium iodide staining. Flow cytometry was used to detect the different cell cycle stages. Western blotting was performed to analyze the protein expression levels of poly(ADP­ribose) polymerase 1 (PARP­1), caspase­3, ­9 and DNA (cytosine­5­)­methyltransferase 1 (DNMT1). Reverse transcription­quantitative polymerase chain reaction was used to assess DNMT1 gene expression. The combination of DAC and BTZ increased the proliferation inhibition, apoptotic rate and G0­G1 arrest compared with use of a single therapeutic agent. In addition, the combination treatment enhanced PARP­1 cleavage, caspase­3 and caspase­9 activation and downregulated the protein and mRNA expression levels of DNMT1. Therefore, the current study determined that the combination of BTZ and the epigenetic agent DAC may be a novel therapeutic strategy to improve the efficacy of BTZ in patients with MM.

Lysosomal ATP imaging in living cells by a water-soluble cationic polythiophene derivative.

Lysosomes in astrocytes and microglia can release ATP as the signaling molecule for the cells through ca(2+)-dependent exocytosis in response to various stimuli. At present, fluorescent probes that can detect ATP in lysosomes have not been reported. In this work, we have developed a new water-soluble cationic polythiophene derivative that can be specifically localized in lysosomes and can be utilized as a fluorescent probe to sense ATP in cells. PEMTEI exhibits high selectivity and sensitivity to ATP at physiological pH values and the detection limit of ATP is as low as 10(-11)M. The probe has low cytotoxicity, good permeability and high photostability in living cells and has been applied successfully to real-time monitoring of the change in concentrations of ATP in lysosomes though fluorescence microscopy. We also demonstrated that lysosomes in Hela cells can release ATP through Ca(2+)-dependent exocytosis in response to drug stimuli.

Tongguan Liqiao acupuncture therapy improves dysphagia after brainstem stroke.

Tongguan Liqiao acupuncture therapy has been shown to effectively treat dysphagia after stroke-based pseudobulbar paralysis. We presumed that this therapy would be effective for dysphagia after bulbar paralysis in patients with brainstem infarction. Sixty-four patients with dysphagia following brainstem infarction were recruited and divided into a medulla oblongata infarction group (n = 22), a midbrain and pons infarction group (n = 16), and a multiple cerebral infarction group (n = 26) according to their magnetic resonance imaging results. All patients received Tongguan Liqiao acupuncture for 28 days. The main acupoints were Neiguan (PC6), Renzhong (DU26), Sanyinjiao (SP6), Fengchi (GB20), Wangu (GB12), and Yifeng (SJ17). Furthermore, the posterior pharyngeal wall was pricked. Before and after treatment, patient swallowing functions were evaluated with the Kubota Water Test, Fujishima Ichiro Rating Scale, and the Standard Swallowing Assessment. The Barthel Index was also used to evaluate their quality of life. Results showed that after 28 days of treatment, scores on the Kubota Water Test and Standard Swallowing Assessment had decreased, but scores on the Fujishima Ichiro Rating Scale and Barthel Index had increased in each group. The total efficacy rate was 92.2% after treatment, and was most obvious in patients with medulla oblongata infarction (95.9%). These findings suggest that Tongguan Liqiao acupuncture therapy can repair the connection of upper motor neurons to the medulla oblongata motor nucleus, promote the recovery of brainstem infarction, and improve patient's swallowing ability and quality of life.

miR-320a affects spinal cord edema through negatively regulating aquaporin-1 of blood-spinal cord barrier during bimodal stage after ischemia reperfusion injury in rats.

BACKGROUND: Spinal cord edema is a serious complication and pathophysiological change after ischemia reperfusion (IR) injury. It has been demonstrated closely associated with bimodal disruption of blood-spinal cord barrier (BSCB) in our previous work. Aquaporin (AQP)1 plays important but contradictory roles in water homeostasis. Recently, microRNAs (miRs) effectively regulate numerous target mRNAs during ischemia. However, whether miRs are able to protect against dimodal disruption of BSCB by regulating perivascular AQP1 remains to be elucidated. RESULTS: Spinal water content and EB extravasation were suggested as a bimodal distribution in directly proportion to AQP1, since all maximal changes were detected at 12 and 48 h after reperfusion. Further TEM and double immunofluorescence showed that former disruption of BSCB at 12 h was attributed to cytotoxic edema by up-regulated AQP1 expressions in astrocytes, whereas the latter at 48 h was mixed with vasogenic edema with both endothelial cells and astrocytes involvement. Microarray analysis revealed that at 12 h post-injury, ten miRs were upregulated (>2.0 fold) and seven miRs were downregulated (<0.5 fold) and at 48 h, ten miRs were upregulated and eleven were downregulated compared to Sham-operated controls. Genomic screening and luciferase assays identified that miR-320a was a potential modulator of AQP1 in spinal cord after IR in vitro. In vivo, compared to rats in IR and negative control group, intrathecal infusion of miR-320a mimic attenuated IR-induced lower limb motor function deficits and BSCB dysfunction as decreased EB extravasation and spinal water content through down-regulating AQP1 expressions, whereas pretreated with miR-320a AMO reversed above effects. CONCLUSION: These findings indicate miR-320a directly and functionally affects spinal cord edema through negatively regulating AQP1 of BSCB after IR.

BODIPY-based azamacrocyclic ensemble for selective fluorescence detection and quantification of homocysteine in biological applications.

Considering the significant role of plasma homocysteine in physiological processes, two ensembles (F465-Cu(2+) and F508-Cu(2+)) were constructed based on a BODIPY (4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene) scaffold conjugated with an azamacrocyclic (1,4,7-triazacyclononane and 1,4,7,10-tetraazacyclododecane) Cu(2+) complex. The results of this effort demonstrated that the F465-Cu(2+) ensemble could be employed to detect homocysteine in the presence of other biologically relevant species, including cysteine and glutathione, under physiological conditions with high selectivity and sensitivity in the turn-on fluorescence mode, while the F508-Cu(2+) ensemble showed no fluorescence responses toward biothiols. A possible mechanism for this homocysteine-specific specificity involving the formation of a homocysteine-induced six-membered ring sandwich structure was proposed and confirmed for the first time by time-dependent fluorescence spectra, ESI-MS and EPR. The detection limit of homocysteine in deproteinized human serum was calculated to be 241.4 nM with a linear range of 0-90.0 µM and the detection limit of F465 for Cu(2+) is 74.7 nM with a linear range of 0-6.0 µM (F508, 80.2 nM, 0-7.0 µM). We have demonstrated the application of the F465-Cu(2+) ensemble for detecting homocysteine in human serum and monitoring the activity of cystathionine ß-synthase in vitro.