DEX Inhibits H/R-induced Cardiomyocyte Ferroptosis by the miR-141-3p/lncRNA TUG1 Axis.

BACKGROUND: Ferroptosis is emerging as a critical pathway in ischemia/reperfusion (I/R) injury, contributing to compromised cardiac function and predisposing individuals to sepsis and myocardial failure. The study investigates the underlying mechanism of dexmedetomidine (DEX) in hypoxia/reoxygenation (H/R)-induced ferroptosis in cardiomyocytes, aiming to identify novel targets for myocardial I/R injury treatment. METHODS: H9C2 cells were subjected to H/R and treated with varying concentrations of DEX. Additionally, H9C2 cells were transfected with miR-141-3p inhibitor followed by H/R treatment. Levels of miR-141-3p, long noncoding RNA (lncRNA) taurine upregulated 1 (TUG1), Fe2+, glutathione (GSH), and malondialdehyde were assessed. Reactive oxygen species (ROS) generation was measured via fluorescent labeling. Expression of ferroptosis-related proteins glutathione peroxidase 4 (GPX4) and acyl-CoA synthetase long-chain family member 4 (ACSL4) was determined using Western blot. The interaction between miR-141-3p and lncRNA TUG1 was evaluated through RNA pull-down assay and dual-luciferase reporter gene assays. The stability of lncRNA TUG1 was assessed using actinomycin D. RESULTS: DEX ameliorated H/R-induced cardiomyocyte injury and elevated miR-141-3p expression in cardiomyocytes. DEX treatment increased cell viability, Fe2+, and ROS levels while decreasing ACSL4 protein expression. Furthermore, DEX upregulated GSH and GPX4 protein levels. miR-141-3p targeted lncRNA TUG1, reducing its stability and overall expression. Inhibition of miR-141-3p or overexpression of lncRNA TUG1 partially reversed the inhibitory effect of DEX on H/R-induced ferroptosis in cardiomyocytes. CONCLUSION: DEX mitigated H/R-induced ferroptosis in cardiomyocytes by upregulating miR-141-3p expression and downregulating lncRNA TUG1 expression, unveiling a potential therapeutic strategy for myocardial I/R injury.

The immune response of Locusta migratoria manilensis at different times of infection with Paranosema locustae.

Paranosema locustae is an entomopathogenic microsporidia with promising potential for controlling agricultural pests, including Locusta migratoria manilensis. However, it has the disadvantage of having a slow insecticidal rate, and how P. locustae infection impacts the host immune response is currently unknown. The present study investigated the effect of P. locustae on the natural immune response of L. migratoria and the activities of enzymes that protect against oxidative stress. Infection with P. locustae increased the hemocytes and nodulation number of L. migratoria at the initial stage of infection. The hemocyte-mediated modulation of immune response was also affected by a decrease in the number of hemocytes 12 days postinfection. Superoxide dismutase activity in locusts increased in the early stages of infection but decreased in the later stages, whereas the activities of peroxidase (POD) and catalase (CAT) showed opposite trends may be due to their different mechanisms of action. Furthermore, the transcription levels of mRNA of antimicrobial peptide-related genes and phenoloxidase activity in hemolymph in L. migratoria were suppressed within 15 days of P. locustae infection. Overall, our data suggest that P. locustae create a conducive environment for its own proliferation in the host by disrupting the immune defense against it. These findings provide useful information for the potential application of P. locustae as a biocontrol agent.

Nardostachys jatamansi and levodopa combination alleviates Parkinson's disease symptoms in rats through activation of Nrf2 and inhibition of NLRP3 signaling pathways.

CONTEXT: Levodopa combined with traditional Chinese medicine has a synergistic effect on Parkinson's disease (PD). Recently, we demonstrated that Nardostachys jatamansi (D. Don) DC. [syn. Patrinia jatamansi D.Don, N. grandiflora DC.] (Valerianaceae) (NJ) can alleviate PD. OBJECTIVE: To explore the synergistic effect of NJ combined with levodopa against PD. MATERIALS AND METHODS: The PD model was established by injecting rotenone. Eighty-four Sprague-Dawley rats were randomly divided into seven groups: sham, model, different doses of NJ (0.31, 0.62, or 1.24 g/kg) combined with levodopa (25 mg/kg), and levodopa alone (25 and 50 mg/kg) groups. The synergistic effect of the combination was investigated by pharmacodynamic investigation and detection of expression of nuclear factor erythro2-related factor 2 (Nrf2) and NLR family proteins containing Pyrin-related domain 3 (NLRP3) pathways. RESULTS: Compared with the model group, NJ + levodopa (1.24 g/kg + 25 mg/kg) increased the moving distance of PD rats in the open field (2395.34 ± 668.73 vs. 1501.41 ± 870.23, p < 0.01), enhanced the stay time on the rotating rod (84.86 ± 18.15 vs. 71.36 ± 17.53, p < 0.01) and the combination was superior to other treatments. The synergistic effects were related to NJ + levodopa (1.24 g/kg + 25 mg/kg) increasing the neurotransmitter levels by 38.80%-88.67% in PD rats, and inhibiting oxidative stress and NLRP3 pathway by activating Nrf2 pathway. DISCUSSION AND CONCLUSIONS: NJ combined with levodopa is a promising therapeutic candidate for PD, which provides a scientific basis for the subsequent clinical combination therapy of levodopa to enhance the anti-PD effect.

11-Ethoxyviburtinal improves chronic restraint stress-induced anxiety-like behaviors in gender-specific mice via PI3K/Akt and E2 /ERß signaling pathways.

Anxiety disorder is a chronic and disabling psychiatric disorder that is more prevalent in females than in males. 11-Ethoxyviburtinal is an iridoid extracted from Valeriana jatamansi Jones, which has anxiolytic potential. The aim of the present work was to study the anxiolytic efficacy and mechanism of 11-ethoxyviburtinal in gender-specific mice. We first evaluated the anxiolytic-like efficacy of 11-ethoxyviburtinal in chronic restraint stress (CRS) mice of different sexes through behavioral experiments and biochemical indexes. In addition, network pharmacology and molecular docking were used to predict potential targets and important pathways for the treatment of anxiety disorder with 11-ethoxyviburtinal. Finally, the influence of 11-ethoxyviburtinal on phosphoinositide-3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, estrogen receptor ß (ERß) expression, and anxiety-like behavior in mice was verified by western blotting, immunohistochemistry staining, antagonist intervention methods, and behavioral experiments. 11-ethoxyviburtinal alleviated the anxiety-like behaviors induced by CRS and inhibited neurotransmitter dysregulation and HPA axis hyperactivity. It inhibited the abnormal activation of the PI3K/Akt signaling pathway, modulated estrogen production, and promoted ERß expression in mice. In addition, the female mice may be more sensitive to the pharmacological effects of 11-ethoxyviburtinal. 11-ethoxyviburtinal may exert its anxiolytic-like effects through PI3K/Akt and E2/ERß signaling pathways. Meanwhile, by comparing the male and female mice, gender differences may affect the therapy and development of anxiety disorder.

Nootkatone alleviates rotenone-induced Parkinson's disease symptoms through activation of the PI3K/Akt signaling pathway.

Parkinson's disease (PD) is the second most common neurodegenerative disease worldwide. Nootkatone (NKT) has been shown to have neuroprotective, anti-inflammatory, and antioxidant effects and in this study, we systematically studied the efficacy and mechanism of action of NKT in rotenone (ROT)-induced PD rats. Firstly, through behavioral experiments and brain tissue staining, we found that NKT alleviated behavioral dysfunction and protected dopaminergic neurons associated with ROT-induced PD rats. Next, target prediction, protein-protein interaction (PPI), Gene Ontology (GO), and pathway enrichment analyses were used to obtain potential targets, specific biological processes, and molecular mechanisms of NKT for the potential treatment of PD. Furthermore, we also applied molecular docking to predict the binding capacity of NKT and related targets. Additionally, in vivo experiments confirmed that NKT could inhibit the expression of Mitogen-activated protein kinase 3 (MAPK3) by activating the PI3K/Akt signaling pathway, reducing neuroinflammation, and ultimately ameliorating ROT-induced PD symptoms. Taken together, the results of the study provide a clear explanation for the remission of PD symptoms by NKT, suggesting that it may be a promising candidate for the treatment of PD.

Nardosinone regulates the slc38a2 gene to alleviate Parkinson's symptoms in rats through the GABAergic synaptic and cAMP pathways.

In a rotenone-induced Parkinson's disease (PD) rat model, behavioral investigation, pathological examination, inflammatory factor analysis, and mitochondrial structure and function investigation verified the anti-PD efficacy of nardosinone. A combined transcriptome and proteome analysis proposed that the anti-PD target of nardosinone is the slc38a2 gene and may involve the GABAergic synaptic pathway and cAMP-signaling pathway. Analysis of targeted slc38a2 knockout cells and expression of key enzyme-encoding genes in both pathways verified the target and pathways proposed by the 'omics analysis. This further confirms that nardosinone can regulate the slc38a2 gene, a potential new target for the treatment of Parkinson's disease, and plays an anti-PD role through the GABAergic synaptic and cAMP pathways.

Dose Optimization of Anxiolytic Compounds Group in Valeriana jatamansi Jones and Mechanism Exploration by Integrating Network Pharmacology and Metabolomics Analysis.

Anxiety disorder impacts the quality of life of the patients. The 95% ethanol extract of rhizomes and roots of Valeriana jatamansi Jones (Zhi zhu xiang, ZZX) has previously been shown to be effective for the treatment of anxiety disorder. In this study, the dose ratio of each component of the anxiolytic compounds group (ACG) in a 95% ethanol extract of ZZX was optimized by a uniform design experiment and mathematical modeling. The anxiolytic effect of ACG was verified by behavioral experiments and biochemical index measurement. Network pharmacology was used to determine potential action targets, as well as predict biological processes and signaling pathways, which were then verified by molecular docking analysis. Metabolomics was then used to screen and analyze metabolites in the rat hippocampus before and after the administration of ZZX-ACG. Finally, the results of metabolomics and network pharmacology were integrated to clarify the anti-anxiety mechanism of the ACG. The optimal dose ratio of ACG in 95% ethanol extract of ZZX was obtained, and our results suggest that ACG may regulate ALB, AKT1, PTGS2, CYP3A4, ESR1, CASP3, CYP2B6, EGFR, SRC, MMP9, IGF1, and MAPK8, as well as the prolactin signaling pathway, estrogen signaling pathway, and arachidonic acid metabolism pathway, thus affecting the brain neurotransmitters and HPA axis hormone levels to play an anxiolytic role, directly or indirectly.

[Effects of Nardostachys jatamansi on gut microbiota of rats with Parkinson's disease].

Under the guidance of the traditional Chinese medicine(TCM) theory of "Zangfu-organs of spleen and stomach" and the modern theory of "microbiota-gut-brain axis", this study explored the effects of Nardostachys jatamansi on the gut microbiota of rats with Parkinson's disease(PD). The 40 SD rats were randomly divided into the control group, PD model group, levodopa group, and Nardostachys jatamansi ethanol extract group. The PD model was established by subcutaneous injection of rotenone in the neck and back area. After 14 days of intragastric administration, the PD rats' behaviors were analyzed through open field test, inclined plane test, and pole test. After the behavioral tests, the striatum, colon, and colon contents of rats in each group were collected. Western blot was employed to detect the protein expression of tyrosine hydroxylase(TH) and α-synuclein(α-syn) in striatum and that of α-syn in colon. Enzyme linked immunosorbent assay(ELISA) was used to detect the levels of tumor necrosis factor-α(TNF-α), interleukin-1ß(IL-1ß), and nuclear factor-kappa B(NF-κB) in striatum and colon. High-throughput sequencing of 16 S rRNA gene was conducted to detect the differences in microbial diversity, abundance, differential phyla, and dominant bacteria of rats between groups. The results indicated that Nar. ethanol extract could relieve dyskinesia, reverse the increased levels of α-syn, TNF-α, IL-1ß, and NF-κB in striatum, and improve the protein expression of TH in striatum of PD rats. The α diversity analysis indicated a significant decrease in diversity and abundance of gut microbiota in the PD model. The results of linear discriminant analysis effect size(LEfSe) of dominant bacteria indicated that Nardostachys jatamansi ethanol extract increased the relative abundance of Clotridiaceae, Lachnospiraceae, and Anaerostipes, and reversed the increased relative abundance of Proteobacteria, Gammaproteobacteria, Enterobacteriaceae, and Escherichia-Shigella in PD model group to exhibit the neuroprotective effect. In summary, the results indicated that Nar. ethanol extract exert the therapeutic effect on PD rats. Specifically, the extract may regulate gut microbiota, decrease the levels of proinflammatory cytokines, and reduce the protein aggregation of α-syn in the colon and striatum to alleviate intestinal inflammation and neuroinflammation. This study provides a basis for combining the theory of "Zangfu-organs of spleen and stomach" with the theory of "microbiota-gut-brain axis" to treat PD.

Valeriana jatamansi Jones ex Roxb. Against Post-Traumatic Stress Disorder, Network Pharmacological Analysis, and In Vivo Evaluation.

Zhi zhu xiang (ZZX) is the root and rhizome of Valeriana jatamansi Jones ex Roxb. Recent studies have shown that ZZX can exert antianxiety, antidepressant, and sedative effects. Because post-traumatic stress disorder (PTSD) is similar to depression and anxiety in terms of its etiology, pathogenesis, and clinical manifestations, it is possible that ZZX may also be useful for the prevention and treatment of PTSD. In this study, a mouse model of PTSD was established and used to study the pharmacological action of a 95% ethanol extract of ZZX on PTSD via a series of classic behavioral tests. We found that a 95% ethanol extract of ZZX was indeed effective for relieving the symptoms of PTSD in mice. Moreover, network pharmacology analysis was used to predict the potential active ingredients, targets, and possible pathways of ZZX in the treatment of PTSD. The neurotransmitter system, the hypothalamic-pituitary-adrenal (HPA) axis, and the endocannabinoid (eCB) system were identified to be the most likely pathways for anti-PTSD action in ZZX. Due to the lack of a falsification mechanism in network pharmacology, in vivo tests were carried out in mice, and the expression levels of neurotransmitters, hormones, and genes of key targets were detected by enzyme-linked immunosorbent assay and real-time PCR to further verify this inference. Analysis showed that the levels of norepinephrine, 5-hydroxytryptamine, and glutamic acid were increased in the hippocampus, prefrontal cortex, and amygdala of PTSD mice, while the levels of dopamine and γ-aminobutyric acid were decreased in these brain regions; furthermore, ZZX could restore the expression of these factors, at least to a certain extent. The levels of adrenocorticotropic hormone, corticosterone, and corticotropin-releasing hormone were increased in these different brain regions and the serum of PTSD mice; these effects could be reversed by ZZX to a certain extent. The expression levels of cannabinoid receptor 1 and diacylglycerol lipase α mRNA were decreased in PTSD mice, while the levels of fatty acid amide hydrolase and monoacylglycerol lipase mRNA were increased; these effects were restored by ZZX to a certain extent. In conclusion, our findings suggest that ZZX may provide new therapeutic pathways for treating PTSD by the regulation of neurotransmitters, the HPA, and expression levels of eCB-related genes in the brain.

[Spectrum-effect relationship of hemostatic effects of Notoginseng Radix et Rhizoma with different commodity specifications].

This article aims to establish the fingerprints, determine the hemostatic pharmacodynamic indicators, and explore the spectrum-effect relationship of Notoginseng Radix et Rhizoma in 12 different specifications. Firstly, HPLC and liquid chromatography-mass spectrometry(LC-MS) were employed to establish the fingerprints of Notoginseng Radix et Rhizoma. The rat plasma recalcification experiment and the rat gastric bleeding experiment were conducted to determine the pharmacodynamic indicators, including plasma recalcification time(PRT), thrombin time(TT), prothrombin time(PT), and activated partial thromboplastin time(APTT). Afterwards, the partial least squares method was employed to explore the spectrum-effect relationship of Notoginseng Radix et Rhizoma in different specifications. Twenty-six common peaks were detected in the HPLC fingerprints of different specifications of Notoginseng Radix et Rhizoma, and 11 out of the 26 common peaks represented saponins. The content of dencichine was determined by LC-MS. The rat experiments showed that the pharmacodynamic indicators were significantly different among different specifications of Notoginseng Radix et Rhizoma. The spectrum-effect relationship was explored between 27 common components and pharmacodynamic indicators. Among them, 16 components had positive effects on the pharmacodynamic indicators of Notoginseng Radix et Rhizoma, and 11 exerted negative effects. This study provides a basis for the precision medication and quality control of Notoginseng Radix et Rhizoma.

[Study on mechanism of Valerianae Jatamansi Rhizoma et Radix against post-traumatic stress disorder based on molecular docking and network pharmacology].

This paper aims to investigate the active components and mechanism of Valerianae Jatamansi Rhizoma et Radix against post-traumatic stress disorder(PTSD) based on network pharmacology and molecular docking. The main components and targets of Valerianae Jatamansi Rhizoma et Radix were obtained by literature mining methods, SwissTargetPrediction, BATMAN and ETCM database. PTSD-related genes were collected from DrugBank, TTD and CTD databases. The protein-protein interaction(PPI) network was constructed based on STRING, and the core targets of Valerianae Jatamansi Rhizoma et Radix in the treatment of PTSD were selected according to the topological parameters. Cytoscape 3.7.2 was used to construct the compound-target network. DAVID database was used for GO enrichment analysis and KEGG enrichment analysis. The relationship network of "compound-target-pathway" was constructed through Cytoscape 3.7.2 to analyze and obtain the key targets and their corresponding components in the network, and their results were verified by molecular docking. The results showed that a total of 47 components(such as valeraldehyde, dihydrovalerin, valerate, chlorovaltrate K, 8-hydroxypinoresinol, 6-hydroxyluteolin, apigenin, farnesin, vanillin, luteolin, kaempferol, glycosmisic acid and pogostemon) of Valerianae Jatamansi Rhizoma et Radix may act on 94 key targets such as CNR1, MAOA, NR3 C1, MAPK14, MAPK8, HTR2 C and DRD2. Totally 29 GO terms were obtained by GO functional enrichment analysis(P<0.05), and 20 signaling pathways were obtained from KEGG pathway enrichment, mainly involving neuroactive ligand-receptor interaction, serotonergic synapse, calcium signaling pathway, cAMP signaling pathway, dopaminergic synapse, retrograde endocannabinoid signaling, neurotrophin signaling pathway, gap junction, cholinergic synapse, estrogen signaling pathway, glutamatergic synapse and long-term potentiation. Molecular docking analysis showed that hydrogen bonding, π-π interaction and hydrophobic effecting may be the main forms of interaction. This study used the network of compound-target-pathway and molecular docking technology to screen the effective components of Valerianae Jatamansi Rhizoma et Radix against PTSD, and explore its anti-PTSD mechanism, so as to provide scientific basis for exploring the anti-PTSD drugs from traditional Chinese medicine and clarifying its mechanism of action.

JAB1 is Involved in Neuropathic Pain by Regulating JNK and NF-κB Activation After Chronic Constriction Injury.

Neuropathic pain, caused by a lesion or dysfunction of the somatosensory nervous system, is a severe debilitating condition with which clinical treatment remains challenging. Jun activation domain-binding protein (JAB1) is a multifunctional protein that participates in several signaling pathways, controlling cell proliferation and apoptosis. However, the expression and possible function of JAB1 in the pathogenesis of neuropathic pain has not been elucidated. This study aimed to investigate the possible involvement of JAB1. Here, employing a neuropathic pain model induced by chronic constriction injury (CCI) on rats, we reported the role of JAB1 in the maintenance of neuropathic pain. By western blot, we found that CCI markedly up-regulated JAB1 expression in the dorsal root ganglion (DRG) and spinal cord. Immunofluorescent assay demonstrated that JAB1 was extensively localized in IB4-, CGRP- and NF200-positive neurons in the injured L5 DRG, and mainly co-localized with NeuN in spinal cord. In addition, we showed that CCI induced phosphorylation of p65 and JNK in vivo. Intrathecal injection of JAB1 siRNA significantly attenuated the CCI-induced JNK and p65 phosphorylation and alleviated both mechanical allodynia and heat hyperalgesia in rats. Taken together, these results suggested that JAB1 promotes neuropathic pain via positively regulating JNK and NF-κB activation.

Rapid quantification of free cholesterol in tears using direct insertion/electron ionization-mass spectrometry.

PURPOSE: To establish a simple and rapid analytical method, based on direct insertion/electron ionization-mass spectrometry (DI/EI-MS), for measuring free cholesterol in tears from humans and rabbits. METHODS: A stable-isotope dilution protocol employing DI/EI-MS in selected ion monitoring mode was developed and validated. It was used to quantify the free cholesterol content in human and rabbit tear extracts. Tears were collected from adult humans (n = 15) and rabbits (n = 10) and lipids extracted. RESULTS: Screening, full-scan (m/z 40-600) DI/EI-MS analysis of crude tear extracts showed that diagnostic ions located in the mass range m/z 350 to 400 were those derived from free cholesterol, with no contribution from cholesterol esters. DI/EI-MS data acquired using selected ion monitoring (SIM) were analyzed for the abundance ratios of diagnostic ions with their stable isotope-labeled analogues arising from the D6-cholesterol internal standard. Standard curves of good linearity were produced and an on-probe limit of detection of 3 ng (at 3:1 signal to noise) and limit of quantification of 8 ng (at 10:1 signal to noise). The concentration of free cholesterol in human tears was 15 ± 6 µg/g, which was higher than in rabbit tears (10 ± 5 µg/g). CONCLUSIONS: A stable-isotope dilution DI/EI-SIM method for free cholesterol quantification without prior chromatographic separation was established. Using this method demonstrated that humans have higher free cholesterol levels in their tears than rabbits. This is in agreement with previous reports. This paper provides a rapid and reliable method to measure free cholesterol in small-volume clinical samples.

Tear film break-up time in rabbits.

BACKGROUND: Rabbits have a longer inter-blink time (approximately 10 minutes) compared with humans (five to eight seconds), suggesting that rabbits have a much more stable tear film. Using fluorescein, the tear break-up time of rabbits has been reported to be similar to that of humans. This study set out to measure the tear break-up time in rabbits using non-invasive methods and to establish the pattern of tear break-up compared to humans. METHODS: The tear break-up time was measured and the pattern of tear break-up was observed in six New Zealand White rabbits on two separate occasions using both the Keeler Tearscope-plus(TM) and a slitlamp biomicroscope. RESULTS: The mean rabbit tear break-up time was 29.8 ± 3.4 (SD) minutes. This contrasts with the reports of human tear break-up time of eight to 30 seconds. The tear breaking spread very slowly and was often restricted to the area of the initial break. CONCLUSION: Rabbit tears have a significantly higher tear break-up time than humans and this aligns with previously demonstrated differences in inter-blink time between rabbits and humans. Understanding the underlying mechanisms of tear stability may lead to novel ways of increasing human tear film stability.

Divalent cations in tears, and their influence on tear film stability in humans and rabbits.

PURPOSE: Reduced tear film stability is reported to contribute to dry eye. Rabbits are known to have a more stable tear film than humans. Thus, we sought to examine the tears of rabbits and humans for metal cations, and to test how they influence tear film stability. METHODS: Tears were collected from 10 healthy humans and 6 rabbits. Tear osmolality was measured by vapor pressure osmometer, and metals analyzed using inductively coupled plasma (ICP) mass spectrometry or ICP atomic emission spectroscopy. The influence of divalent cations on tears was analyzed by measuring surface tension using the Langmuir trough in vitro, using different concentrations of cations in the subphase, and grading the tear break-up in rabbits in vivo after instillation of chelating agents. RESULTS: Rabbit tears had a higher osmolality compared to humans. Major metals did not differ between species; however, rabbits had higher levels of Mg(2+) (1.13 vs. 0.39 mM) and Ca(2+) (0.75 vs. 0.36 mM). In rabbit tears in vitro, diminishing divalent cations resulted in a decrease in the maximum surface pressure from 37 to 30 mN/m. In vivo, an increase in the amount of tear film that was broken-up was found. In contrast, when changing divalent cation concentrations in human tears, the maximum surface pressure remained at 26 mN/m. CONCLUSIONS: The normal osmolality of rabbit tears is significantly higher than that in humans. While divalent cations had little influence on human tears, they appear to have an important role in maintaining tear film stability in rabbits.

Contact lens deposits, adverse responses, and clinical ocular surface parameters.

PURPOSE: To correlate clinical responses during contact lens wear with the amount of protein or cholesterol extracted from lenses after wear. METHODS: Clinical parameters, including adverse response rates and corneal staining, and symptomatology rating during lens wear were collected from a series of clinical tests comprising four different silicone hydrogel lenses with four different multipurpose solutions. To test for correlates, the amount of total protein or cholesterol extracted from lenses after daily wear were compared statistically to clinical parameters. RESULTS: The amount of protein (p = 0.008) or cholesterol (p = 0.01) extracted from lenses was higher for those subjects who showed solution-induced corneal staining. Amount of protein extracted was correlated (p < 0.01) with conjunctival staining (R = -0.23), lens front surface wetting (r = 0.14), and lens fit tightness (R = -0.20). These clinical parameters accounted for 48% of lens protein deposition. The amount of cholesterol extracted from lenses was much more weakly associated with clinical variables. Amount of protein or cholesterol extracted from lenses was not associated with the production of any corneal infiltrative or mechanical adverse event during wear and was only very weakly correlated with insertion comfort of lenses. CONCLUSIONS: These results suggest that there may be no physiologically relevant consequence of cholesterol depositing on silicone hydrogel lenses. The amount of protein that deposits onto silicone hydrogel lenses during wear may have more affect on lens performance on-eye. However, the correlations were generally small and may still not indicate any causative relevant physiological response. Further work is required to determine whether there is any direct causative effect to support these correlative findings.

Care regimen and lens material influence on silicone hydrogel contact lens deposition.

PURPOSE: To quantitatively detect proteins and cholesterol extracted from worn silicone hydrogel contact lenses and determine the effect of various lens care solutions on deposit accumulation. METHODS: Contact lenses, made from different polymers and worn on a daily wear schedule with different lens care solutions, were collected. Lipid and protein deposits were extracted by methanol:chloroform (1:1, v/v) and protein extraction solution (containing urea and surfactant), respectively. Lipid extracts were separated and cholesterol quantified using thin layer chromatography. Protein extracts were quantified using standard techniques. RESULTS: Among all lenses tested, Balafilcon A lenses exhibited greatest extracted cholesterol (4.1 to 8.2 microg/lens) and total protein (5.4 to 23.2 microg/lens). AQuify was the most effective solution in reducing extracted deposits, especially extracted protein, from Balafilcon A lenses. AQuify and Opti-Free RepleniSH solutions were most effective in reducing extracted cholesterol from Senofilcon A and Galyfilcon A lenses, respectively. Use of Opti-Free Express solution resulted in more extracted protein from Lotrafilcon B lenses than use of other solutions. Generally, Lotrafilcon B, Senofilcon A, and Galyfilcon A lenses accumulated relatively low amount of proteins. Lotrafilcon B lenses accumulated the least amount of cholesterol deposit among all lenses tested regardless of solution used. CONCLUSIONS: Lens polymer (possibly associated with surface characteristics) is a prominent factor affecting lipid and protein accumulation. Within a lens polymer type, lens care solutions exhibit varying effectiveness in reducing protein and lipid accumulation.

Proteomic analysis of protein deposits on worn daily wear silicone hydrogel contact lenses.

PURPOSE: Previous studies have demonstrated deposition of tear proteins onto worn contact lenses. In this study, we used proteomic techniques to analyze the protein deposits extracted from worn daily wear silicone hydrogel contact lenses in combination with different lens care solutions. METHODS: Worn lenses were collected and protein deposits extracted using urea and surfactant. Protein extracts were desalted, concentrated, and then separated using one-dimensional gel electrophoresis. Individual protein components in extracts were identified using liquid chromatography combined with tandem mass spectrometry (LC-MS-MS) after trypsin digestion. RESULTS: One-dimensional gel electrophoresis revealed that lysozyme and other small proteins (around 20 kDa) were the most abundant proteins in the extracts. LC-MS-MS revealed a wide array of proteins in lens extracts with lysozyme and lipocalin 1 being the most commonly identified in deposit extracts. CONCLUSIONS: Worn contact lenses deposit a wide array of proteins from tear film and other sources. Protein deposit profiles varied and were specific for each contact lens material.

Human lens lipids differ markedly from those of commonly used experimental animals.

Electrospray ionisation tandem mass spectrometry has allowed the unambiguous identification and quantification of individual lens phospholipids in human and six animal models. Using this approach ca. 100 unique phospholipids have been characterised. Parallel analysis of the same lens extracts by a novel direct-insertion electron-ionization technique found the cholesterol content of human lenses to be significantly higher (ca. 6 times) than lenses from the other animals. The most abundant phospholipids in all the lenses examined were choline-containing phospholipids. In rat, mouse, sheep, cow, pig and chicken, these were present largely as phosphatidylcholines, in contrast 66% of the total phospholipid in Homo sapiens was sphingomyelin, with the most abundant being dihydrosphingomyelins, in particular SM(d18:0/16:0) and SM(d18:0/24:1). The abundant glycerophospholipids within human lenses were found to be predominantly phosphatidylethanolamines and phosphatidylserines with surprisingly high concentrations of ether-linked alkyl chains identified in both classes. This study is the first to identify the phospholipid class (head-group) and assign the constituent fatty acid(s) for each lipid molecule and to quantify individual lens phospholipids using internal standards. These data clearly indicate marked differences in the membrane lipid composition of the human lens compared to commonly used animal models and thus predict a significant variation in the membrane properties of human lens fibre cells compared to those of other animals.