Molecular Probes for Sulfatase Detection and Bio-Imaging.

Arylsulfatases A and B were measured in the stratum corneum of four normal controls and two individuals with sex-linked ichthyosis. For arylsulfatase A, the mean delta optical density/hr/mg protein value was 1.6 for controls and 2.0 for patients, whereas for arylsulfatase B values of 1.5 for controls and 1.4 for patients were observed. Assay of arylsulfatase C in the callus of four normal controls showed a mean delta optical density/hr/100 mg callus of 0.63, whereas no or trace activity was detected in callus from four patients with x-linked ichthyosis. The assay of steroid sulfatase is best for studying microsomal sulfatase activity. Table 1 shows the activity of this enzyme in nails, callus, and hair bulbs from controls and patients with x-linked ichthyosis. No steroid sulfatase could be demonstrated in patients with x-linked ichthyosis. The values in normal controls and obligate heterozygotes are compared in Table 2. The mean value of the two groups is statistically different with P less than or equal to 0.05 using the Student t test.

Paradoxical effect of estradiol: it can block its own bioformation in human breast cancer cells

Steroid sulfatase, arylsulfatases A and B, galactose-6-sulfatase, and iduronate sulfatase in mammary cells and effects of sulfated and non-sulfated estrogens on sulfatase activity

Steroid sulfatase (STS) activity was studied in the Long-Evans rat testis. The rate of dehydroepiandrosterone sulfate (DHA-S) hydrolysis determined in whole testis homogenates was low compared to that of the corresponding microsomal fractions, which was, in contrast, as high as that expressed in homogenates from purified Leydig cells. Such an increment in STS activity between total homogenates and the corresponding microsomes was not observed for the seminiferous tubules. The STS affinity reported for total testicular microsomes (Km = 3.47 +/- 0.54 microM; mean +/- SEM) was of the same magnitude as that previously reported for Leydig cells, but was about 3 times higher than that measured for whole testis homogenate (Km = 10.11 +/- 0.92 microM). In vivo hCG treatment decreased the STS affinity in total testicular microsomes without affecting this kinetic parameter in whole testis homogenate. These data suggest that the steroid sulfatase expressed in total testicular microsomes (activity and regulation by hCG) could be considered as a good index of Leydig cell STS activity.

Inhibition of steroid sulfatase (STS) activity in skin is a potential new treatment strategy for a number of skin disorders, including hirsutism, androgen-dependent alopecia, acne and psoriasis. In skin and its appendages, STS regulates the hydrolysis of dehydroepiandrosterone sulfate to dehydroepiandrosterone, a weak androgen, which can be converted to the biologically active androgens testosterone and 5 alpha-dihydrotestosterone by other steroidogenic enzymes also present in skin. A number of potent, irreversible STS inhibitors have been developed based around a core arylsulfamate ester motif, the active pharmacophore required for potent STS inhibition. Such inhibitors include AHBS and STX-64. Topical application of AHBS to the skin of mice or pigs resulted in almost complete inhibition of skin STS activity. Furthermore, when applied to the skin of Gottingen minipigs daily for 2 weeks, by day 10 AHBS had inhibited sebum production, a desired requisite for an antiacne drug. When applied topically to the skin of nude mice at 1.0 and 10.0 mg/kg STX-64 inhibited skin STS activity by > 90%, but it also inhibited liver STS activity. While preclinical studies have confirmed the ability of topically applied STS inhibitors to inhibit skin STS activity, further studies using preclinical models of skin disorders and clinical trials are needed to test their efficacy in treating skin disorders.

Synthetic bioluminescence reactions exhibiting near-infrared (NIR)-shifted spectra have been explored to improve deep-tissue imaging through the design of firefly luciferin analogues. Although the NIR bioluminescence reactions improve the tissue penetration of bioluminescence signals from deep tissues, their photon output is markedly lower compared to the natural reaction with D-luciferin and firefly luciferase (Fluc), often by an order of magnitude or more. Consequently, in most instances, the sensitivity of NIR bioluminescence imaging (NIR-BLI) has not yet substantially surpassed that of BLI with the natural firefly reaction. Here, we present a synthetic firefly luciferin, named AkaSuke, that generates intense NIR bioluminescence (λmax = 680 nm) in reaction with Fluc, greatly improving the detection sensitivity beyond that of the D-luciferin/Fluc reaction for targeting deep tissue. AkaSuke enables sensitive visualizations of ectopic hematogenesis through entire tissues of mice over time following transplantation of bone marrow stem cells labeled with Fluc. We additionally identify a Japanese firefly luciferase, DkumLuc1, that displays higher catalytic activities for bioluminescence emission of AkaSuke compared to typical Fluc, resulting in detection sensitivity comparable to that of AkaLumine/Akaluc reaction, one of the most sensitive bioluminescence systems for deep tissue imaging. We further propose the potential of the AkaSuke/DkumLuc1 reaction as an orthogonal pair with the AkaLumine/Akaluc for sensitive dual-target tracking in mice. Overall results suggest that AkaSuke enhances the capabilities of deep-tissue bioluminescence imaging using Fluc and its variant, and could serve as an emerging benchmark for the molecular design of NIR luciferin analogues.

SummaryThe ability of human breast tumor preparations to hydrolyze DHEA, estrone, and testosterone sulfates was studied. Of the 85 tumor preparations examined, 31 tumors contained an estrogen sulfatase activity and 19 of which also exhibited sulfatase activity toward DHEA; but there was no testosterone sulfatase in any of the 31 tumor preparations. The remaining 54 tumor preparations showed no sulfatase activity toward any of the three steroid sulfates examined. The present data also disclose that the levels of sulfatase activities do not affect those of sulfotransferase activities in the tumor preparations. Further, the ratio of sulfotransferase activity with DHEA and estradiol as substrates is not related to the sulfatase activity in these tumor preparations.

Abstract: In recent years, the development of convenient and rapid detection technologies has become an urgent priority due to the increasingly severe environmental pollution issues. Among various analytical approaches, the ratiometric fluorescence method (RFLM) is widely applied in the field of environmental pollutant sensing owing to the merits of high sensitivity and anti-interference ability. Firstly, unlike previous work, this review systematically reports the sensing modes of RFLM for the first time, concerning co-directional, contra-directional, and inconstant-constant variation modes. The sensing mechanisms of RFLM are also briefly outlined, such as aggregation-induced emission, intramolecular charge transfer, photoinduced electron transfer, fluorescence resonance energy transfer, and inner filter effect, as well as the molecular imprinting technique. In addition, we discuss the enhancement of artificial intelligence (AI) for the analytical performance of RFLM. Subsequently, the review provides a detailed summary of recent advances over the past five years in RFLM-based applications, with a focus on luminescent materials, including inorganic nanomaterials and organic fluorophores. Finally, we propose the current challenges associated with RFLM in environmental pollutant sensing and outline potential directions for future research and development.

Unique fluorescence of boronic acid derived salicylidenehydrazone complexes with two perpendicular ICT: Solvent effect on PET process

SWR/J mice possess high arylsulfatase C, estrone sulfatase, and dehydroepiandrosterone sulfatase activities in liver, spleen, and kidney compared to A/J mice. This interstrain activity variation appears to be determined by at least 1 autosomal gene. Murine arylsulfatase C activity occurs in both hydrophobic and hydrophilic forms which differ with respect to certain biochemical properties and exhibit different subcellular distributions. The hydrophilic isozyme is a major component in kidney and brain extracts and a minor isozyme in liver and spleen extracts. The hydrophobic arylsulfatase C isozyme appears to be identical to steroid sulfatase. The hydrophilic arylsulfatase C isozyme does not possess steroid sulfatase activity; however, hydrophilic and hydrophobic arylsulfatase C share certain properties, suggesting that they may be structurally related. The autosomal gene(s) affects both arylsulfatase isozymes.

Steroid sulfatase and sulfuryl transferase activities in human brain tumors

The molecular design of functional organic dyes as fluorescent chemosensors represents a dynamic frontier in materials chemistry, bridging synthetic dye chemistry with practical analytical applications. This review summarizes recent progress in the molecular design and photophysical properties of fluorescent sensors for metal ion detection, with particular emphasis on lead (Pb 2+ ) ions. The first part focuses specifically on Pb 2+ -responsive sensors, considering the high toxicity of lead and the need for selective chelation strategies. The second part systematically surveys diverse fluorophore backbones, including quinoline, pyrazoloquinoline, fluorescein, rhodamine, coumarin, pyrene, and Schiff base derivatives. Special attention is given to how specific structural modifications and the strategic incorporation of chelating units influence fluorescence responses and coordination selectivity. Key analytical parameters of sensor–ion systems, such as detection limits, binding constants, and complex stoichiometry, are compared across representative fluorophore-based sensorsFinally, the underlying metal-ligand interactions and fluorescence sensing mechanisms, including photoinduced electron transfer (PET), intramolecular charge transfer (ICT), chelation-enhanced fluorescence (CHEF), chelation-enhanced quenching (CHEQ) and excited state intramolecular proton transfer (ESIPT), are discussed. The review concludes with an outlook on current challenges and future perspectives in the development of selective, sensitive, and practically applicable fluorescent sensors for Pb 2+ detection. • Comprehensive review of organic dye-based fluorescent sensors for metal ion detection, with a specific focus on highly toxic Pb 2+ ions. • Comparison of sensors with different fluorophore cores (fluorescein, rhodamine, quinoline, pyrene, coumarin, Schiff base), including their detection limits, complex stoichiometry, and binding constants. • Detailed overview of the coordination chemistry of Pb 2+ -selective sensors. • Insight into the fluorescence detection mechanism (PET, ICT, CHEF, CHEQ, ESIPT) as a key design element for improving sensor selectivity and sensitivity.

Live-cell imaging of β-galactosidase based on a quinoline-malononitrile-derived AIE probe.

Two probes, AIE-1 and AIE-2, were synthesized to investigate the effect of substitutional functional group on aggregation (aggregation-caused quenching (ACQ) or aggregation-induced emission (AIE)) and intramolecular charge transfer (ICT) behavior as well as on the cell imaging aspect. The yellow-color non-substituted probe AIE-1 showed weak charge-transfer absorption and an emission band at 377 nm and 432 nm, whereas the yellowish-orange color substituted probe AIE-2 showed a strong charge-transfer absorption and an emission band at 424 nm and 477 nm in THF solvent. The UV-Vis studies of AIE-1 and AIE-2 in THF and THF with different water fractions showed huge absorption changes in AIE-2 with high water fractions due to its strong aggregation behavior, but no such noticeable absorption changes were observed for AIE-1. Interestingly, the fluorescence intensity of AIE-1 at 432 nm gradually decreased with increasing water fractions and became almost non-emissive at 90% water. However, the monomer-type emission of AIE-2 at 477 nm was shifted to 584 nm with a 6-fold increase in fluorescence intensity in THF-H2O (1:9, v/v) solvent mixtures due to the restriction of intramolecular rotation on aggregation in high water fractions. This result indicates that the probe AIE-1 shows ACQ and probe AIE-2 shows AIE behaviors in THF-H2O solvent mixtures. Furthermore, the emission spectra of AIE-1 and AIE-2 were carried out in different solvent and with different concentrations to see the solvent- or concentration-dependent aggregation behavior. Scanning electron microscope (SEM) and dynamic light scattering (DLS) experiments were also conducted to assess the morphology and particle size of two probes before and after aggregation. Both of the probes, AIE-1 and AIE-2, showed less toxicity on HeLa cells and were suitable for cell imaging studies. Density functional theory (DFT) calculation was also carried out to confirm the ICT process from an electron-rich indole moiety to an electron-deficient cyano-phenyl ring of AIE-1 or AIE-2.

Characterization of steroid sulfatase in the MC3T3-E1 mouse pre-osteoblastic cell line