Mercury sulfide-containing Hua-Feng-Dan and 70W (Rannasangpei) protect against LPS plus MPTP-induced neurotoxicity and disturbance of gut microbiota in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Mercury sulfides (HgS) are frequently included in Ayurveda, Tibetan and Chinese medicines to assist the presumed therapeutic effects, but the ethnopharmacology remains elusive. The present study examined the protective effects of α-HgS-containing Hua-Feng-Dan and ß-HgS-containing 70 Wei-Zhen-Zhu-Wan (70W, Rannasangpei) against Parkinson's disease mice induced by lipopolysaccharide (LPS) plus 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). METHOD: A single injection of LPS (5 mg/kg ip) was given to adult male C57BL/6 mice, and 150 days later, the low dose of MPTP (15 mg/kg, ip, for 4 days) was given to produce the "two-hit" Parkinson's disease model. Together with MPTP treatment, mice were fed with clinically-relevant doses of Hua-Feng-Dan (0.6 g/kg) and 70W (0.2 g/kg) for 35 days. Rotarod test was performed to examine muscle coordination capability. At the end of the experiment, brain was transcardially perfused with paraformaldehyde, the substantia nigra was sectioned for microglia (Iba1 staining) and dopaminergic neuron (THir staining) determination. Colon bacterial DNA was extracted and subjected to qPCR analysis with 16S rRNA probes. RESULTS: The low-grade, chronic neuroinflammation produced by LPS aggravated MPTP neurotoxicity, as evidenced by decreased motor activity, intensified microglia activation and loss of dopaminergic neurons. Both Hua-Feng-Dan and 70W increased rotarod activity and ameliorated the pathological lesions in the brain. In gut microbiomes examined, LPS plus MPTP increased Verrucomicrobiaceae, Methanobacteriaceae, Pronicromonosporaceae, and Clostridaceae species were attenuated by Hua-Feng-Dan and 70W. CONCLUSIONS: α-HgS-containing Hua-Feng-Dan and ß-HgS-containing 70W at clinical doses protected against chronic LPS plus MPTP-induced toxicity to the brain and gut, suggesting HgS-containing traditional medicines could target gut microbiota as a mechanism of their therapeutic effects.

Different proteomic profiles of cinnabar upon therapeutic and toxic exposure reveal distinctive biological manifestations.

ETHNOPHARMACOLOGICAL RELEVANCE: Cinnabar, a traditional Chinese mineral medicine with sedative and tranquilizing effects, is known to be toxic to the neural system, but its detailed pharmacological and toxicological mechanisms are still unclear. AIM OF THE STUDY: This study aimed to explore the potential neuropharmacological and neurotoxicological mechanisms of cinnabar by investigating the differentially expressed proteins in cerebral cortices of mice exposed to therapeutic and toxic doses of cinnabar. MATERIALS AND METHODS: Label-free quantitative proteomics and bioinformatics analysis were used to characterize the proteins, pathways, and potential targets associated with therapeutic (50 mg/kg) and toxic (1000 mg/kg) doses of cinnabar in cerebral cortices of mice. Proteomic analysis was verified by parallel reaction monitoring. RESULTS: A total of 6370 and 6299 proteins were identified in the cerebral cortices of mice after exposure to therapeutic and toxic doses of cinnabar, among which 130 and 119 proteins were differentially expressed, respectively. Functional/pathway enrichment analysis showed that both exposure doses of cinnabar could affect transport processes in the cerebral cortex through different proteins. The changes induced by the therapeutic dose included pathways involved in translation and sphingolipid metabolism. Interestingly, for the toxic dose, differentially expressed proteins were enriched for functions and pathways related to RNA splicing, transcription, synaptic plasticity regulation and developmental processes, among which RNA splicing was the most significantly affected function. ATP6V1D and CX3CL1 were shown to be possible key proteins affected by cinnabar, leading to multiple functional changes in the cerebral cortex at the therapeutic and toxic doses, respectively. Furthermore, Connectivity Map (CMap) analysis predicted LRRK2 to be a potential therapeutic target and FTase to be a potential toxic target for cinnabar. CONCLUSION: Our results suggest that the pathways and potential targets identified in the mouse cerebral cortex exposed to therapeutic and toxic doses of cinnabar are different, which provides novel insights into the potential molecular mechanisms underlying the pharmacological and toxicological effects of cinnabar.

Protective role of cinnabar and realgar in Hua-Feng-Dan against LPS plus rotenone-induced neurotoxicity and disturbance of gut microbiota in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Hua-Feng-Dan (HFD) is a traditional Chinese medicine used for neurological disorders. HFD contains cinnabar (HgS) and realgar (As4S4). The ethnopharmacological basis of cinnabar and realgar in HFD is not known. AIM OF THE STUDY: To address the role of cinnabar and realgar in HFD-produced neuroprotection against neurodegenerative diseases and disturbance of gut microbiota. MATERIALS AND METHODS: Lipopolysaccharide (LPS) plus rotenone (ROT)-elicited rat dopaminergic (DA) neuronal damage loss was performed as a Parkinson's disease animal model. Rats were given a single injection of LPS. Four months later, rats were challenged with the threshold dose of ROT. The clinical dose of HFD was administered via feed, starting from ROT administration for 46 days. Behavioral dysfunction was detected by rotarod and Y-maze tests. DA neuron loss and microglial activation were assessed via immunohistochemical staining and western bolt analysis. The colon content was collected to extract bacterial DNA followed by real-time PCR analysis with 16S rRNA primers. RESULTS: LPS plus ROT induced neurotoxicity, as evidenced by DA neuron loss in substantia nigra, impaired behavioral functions and increased microglial activation. HFD-original (containing 10% cinnabar and 10% realgar) rescued loss of DA neurons, improved behavioral dysfunction and attenuated microglial activation. Compared with HFD-original, HFD-reduced (3% cinnabar and 3% realgar) was also effective, but to be a less extent, while HFD-removed (without cinnabar and realgar) was ineffective. In analysis of gut microbiome, the increased Verrucomicrobiaceae and Lactobacteriaceae, and the decreased Enterobacteeriaceae by LPS plus ROT were ameliorated by HFD-original, and to be the less extent by HFD-reduced. CONCLUSION: Cinnabar and realgar are active ingredients in HFD to exert beneficial effects in a neurodegenerative model and gut microbiota.

Autophagic elimination of Trypanosoma cruzi in the presence of metals.

Trypanosoma cruzi is an obligate intracellular parasite transmitted to vertebrate hosts by blood-sucking insects. Molecules present in parasites and mammalian cells allow the recognition and parasite internalization. Metallic ions play an essential role in the establishment and maintenance of host-parasite interaction. However, little is known about how parasites handle with essential and nonessential metal quotas. This study aimed to investigate the influence of metal ions on the biological processes of T. cruzi infected cells. Infected cells were incubated with ZnCl2, CdCl2, and HgCl2 for 12 h and labeled with different specific dyes to investigate the cellular events related to intracellular parasite death and elimination. Infected host cells and parasite's mitochondria underwent functional and structural disorders, in addition to parasite's DNA condensation and pH decrease on host cells, which led to parasite death. Further investigations suggested that lysosomes were involved in pH decrease and the double membrane of the endoplasmic reticulum formed vacuoles surrounding damaged parasites, which indicate the occurrence of autophagy for parasite elimination. In conclusion, low concentrations of nonessential and essential metals cause a series of damage to Trypanosoma cruzi organelles, leading to its loss of viability, death, and elimination, with no removal of the host cells.

Realgar and cinnabar are essential components contributing to neuroprotection of Angong Niuhuang Wan with no hepatorenal toxicity in transient ischemic brain injury.

Realgar and cinnabar are commonly used mineral medicine containing arsenic and mercury in Traditional Chinese Medicine (TCM). Angong Niuhuang Wan (AGNHW) is a representative realgar- and cinnabar-containing TCM formula for treating acute ischemic stroke, but its toxicology and neuropharmacological effects are not well addressed. In this study, we compared the neuropharmacological effects of AGNHW and modified AGNHW in an experimental ischemic stroke rat model. Male SD rats were subjected to 2 h of middle cerebral artery occlusion (MCAO) plus 22 h of reperfusion. Although oral administration of AGNHW for 7 days in the rats increased arsenic level in the blood and liver tissue, there were no significant changes in the arsenic level in kidney, mercury level in the blood, liver and kidney as well as hepatic and renal functions in MCAO rats. AGNHW revealed neuroprotective properties by reducing infarction volume, preserving blood-brain barrier integrity and improving neurological functions against cerebral ischemia-reperfusion injury. Interestingly, removing realgar and/or cinnabar from AGNHW abolished the neuroprotective effects. Meanwhile, AGNHW could scavenge peroxynitrite, down-regulate the expression of p47phox, 3-NT and MMP-9 and up-regulate the expression of ZO-1 and claudin-5 in the ischemic brains, which were abolished by removing realgar and/or cinnabar from AGNHW. Notably, realgar or cinnabar had no neuroprotection when used alone. Taken together, oral administration of AGNHW for one week should be safe for treating ischemic stroke with neuroprotective effects. Realgar and cinnabar are necessary elements with synergetic actions with other herbal materials for the neuroprotective effects of AGNHW against cerebral ischemia-reperfusion injury.

Effects of major vein blockage and aquaporin inhibition on leaf hydraulics and stomatal conductance.

The density and architecture of leaf veins determine the network and efficiency of water transport within laminae and resultant leaf gas exchange and vary widely among plant species. Leaf hydraulic conductance ( Kleaf) can be regulated by vein architecture in conjunction with the water channel protein aquaporin. However, our understanding of how leaf veins and aquaporins affect leaf hydraulics and stomatal conductance ( gs) remains poor. By inducing blockage of the major veins and inhibition of aquaporin activity using HgCl2, we examined the effects of major veins and aquaporins on Kleaf and gs in species with different venation types. A vine species, with thick first-order veins and low vein density, displayed a rapidly declined gs with high leaf water potential in response to vein blockage and a greatly reduced Kleaf and gs in response to aquaporin inhibition, suggesting that leaf aquaporins are involved in isohydric/anisohydric stomatal behaviour. Across species, the decline in Kleaf and gs due to aquaporin inhibition increased linearly with decreasing major vein density, possibly indicating that a trade-off function between vein architecture (apoplastic pathway) and aquaporin activity (cell-to-cell pathway) affects leaf hydraulics.

HgS Inhibits Oxidative Stress Caused by Hypoxia through Regulation of 5-HT Metabolism Pathway.

This study aims to reveal the potential relationship between 5-HT and oxidative stress in the organism. Our in vitro experiments in RIN-14B cells showed that anoxia leads the cells to the state of oxidative stress. Administration of exogenous 5-HT exacerbated this effect, whereas the inhibition of Tph1, LP533401 alleviated the oxidative stress. Several research articles reported that Cinnabar (consists of more than 96% mercury sulfide, HgS), which is widely used in both Chinese and Indian traditional medicine prescriptions, has been involved in the regulation of 5-HT. The present research revealed that HgS relieved the level of oxidative stress of RIN-14B cells. This pharmacological activity was also observed in the prescription drug Zuotai, in which HgS accounts for 54.5%, and these effects were found to be similar to LP533401, an experimental drug to treat pulmonary hypertension. Further, our in vivo experiments revealed that the administration of cinnabar or prescription drug Zuotai in zebrafish reduced the reactive oxygen species (ROS) induced by hypoxia and cured behavioral abnormalities. Taken together, in organisms with hypoxia induced oxidative stress 5-HT levels were found to be abnormally elevated, indicating that 5-HT could regulate oxidative stress, and the decrease in the 5-HT levels, behavioral abnormalities after treatment with cinnabar and Zuotai, we may conclude that the therapeutic and pharmacologic effect of cinnabar and Zuotai may be based on the regulation of 5-HT metabolism and relief of oxidative stress. Even though they aren't toxic at the present dosage in both cell lines and zebrafish, their dose dependent toxicities are yet to be evaluated.

Types of antiseptics, presentations and rules of use. / Tipos de antisépticos, presentaciones y normas de uso.

Antiseptics are chemical substances that when applied topically onto intact skin, mucous membranes or wounds partially or completely reduces the population of living microorganisms in those tissues. Different types of antiseptics are available - those most commonly used in clinical practice being alcohols, iodinated compounds and chlorhexidine. When using an antiseptic, consideration is required of its spectrum of antimicrobial activity, latency, residual effects, possible interferences of the presence of organic material with the activity of the antiseptic, its side effects, compatibility with other antiseptics, and cost. This article is part of a supplement entitled "Antisepsis in the critical patient", which is sponsored by Becton Dickinson.

Chiral ß-HgS quantum dots: Aqueous synthesis, optical properties and cytocompatibility.

ß-HgS quantum dots (QDs) have drawn enormous attention due to the size-tunable bandgap and the lowest quantum state in conduction band which have been applied to semiconductor transistor and photodetector. Though ß-HgS is the essential component of Tibetan medicine, the potential toxicity of ß-HgS limits its applications, especially in bio-application. Herein, chiral biomolecule enantiomers N-isobutyryl-L(D)-cysteine (L(D)-NIBC) and L(D)-cysteine (L(D)-Cys) were introduced into HgCl2 and Na2S aqueous solution to synthesize chiral ß-HgS QDs in one-pot, which significantly improved their water-solubility and cytocompatibility. Notably, all chiral ß-HgS QDs showed none cytotoxicity even at high concentration (20 mg·L-1), and the cytocompatibility of D-ß-HgS QDs was better than corresponding L-ß-HgS QDs at the concentration of 20 mg·L-1. This cytotoxicity discrimination was associated with the chirality inversion of chiral ß-HgS QDs compared with the corresponding chiral ligands. In-situ real-time circular dichroism (CD) monitoring indicated that the chirality of ß-HgS QDs originated from the asymmetrical arrangement of chiral ligands on the achiral core surface. Their chiroptical activity, near-infrared optical absorption (800 nm), fluorescence emission (900-1000 nm), high-performance photothermal conversion and good cytocompatibility, implied chiral ß-HgS QDs could be used as a candidate material for photothermal therapy or a near-infrared fluorescent probe in organism, which brings a novel insight for bio-application of ß-HgS QDs.

A review of cinnabar (HgS) and/or realgar (As4S4)-containing traditional medicines.

ETHNOPHARMOCOLOGICAL RELEVANCE: Herbo-metallic preparations have a long history in the treatment of diseases, and are still used today for refractory diseases, as adjuncts to standard therapy, or for economic reasons in developing countries. AIM OF THE REVIEW: This review uses cinnabar (HgS) and realgar (As4S4) as mineral examples to discuss their occurrence, therapeutic use, pharmacology, toxicity in traditional medicine mixtures, and research perspectives. MATERIALS AND METHODS: A literature search on cinnabar and realgar from PubMed, Chinese pharmacopeia, Google and other sources was carried out. Traditional medicines containing both cinnabar and realgar (An-Gong-Niu-Huang Wan, Hua-Feng-Dan); mainly cinnabar (Zhu-Sha-An-Shen Wan; Zuotai and Dangzuo), and mainly realgar (Huang-Dai Pian; Liu-Shen Wan; Niu-Huang-Jie-Du) are discussed. RESULTS: Both cinnabar and realgar used in traditional medicines are subjected to special preparation procedures to remove impurities. Metals in these traditional medicines are in the sulfide forms which are different from environmental mercurials (HgCl2, MeHg) or arsenicals (NaAsO2, NaH2AsO4). Cinnabar and/or realgar are seldom used alone, but rather as mixtures with herbs and/or animal products in traditional medicines. Advanced technologies are now used to characterize these preparations. The bioaccessibility, absorption, distribution, metabolism and elimination of these herbo-metallic preparations are different from environmental metals. The rationale of including metals in traditional remedies and their interactions with drugs need to be justified. At higher therapeutic doses, balance of the benefits and risks is critical. Surveillance of patients using these herbo-metallic preparations is desired. CONCLUSION: Chemical forms of mercury and arsenic are a major determinant of their disposition, efficacy and toxicity, and the use of total Hg and As alone for risk assessment of metals in traditional medicines is insufficient.

[Effect of Zuotai and HgS on gene expression of drug-metabolizing enzymes in livers of mice].

Zuotai and cinnabar(96%HgS) are contained in many traditional medicines. To examine their potential effects on drug metabolism genes, mice were orally given Zuotai or HgS at doses of 10, 30, 100, 300 mg•kg⁻¹ for 7 days. HgCl2(33.6 mg•kg⁻¹) was gavaged for control. Twenty-four hour later after the last administration, livers were collected, and expressions of genes related to metabolic enzymes and transporters were examined. Zuotai and HgS had no effects on major phase-1, phase-2 and transporter genes; HgCl2 increased the expressions of CYP2B10, CYP4A10, OATP1A4, UGT1A1, UGT2A3, SULT1A1, SULT2A1, MRP1, MRP3 and MRP4; expression of OATP1A1 was decreased by HgCl2, but not by Zuotai and HgS. Therefore, Zuotai and HgS have different adverse effects on drug-metabolizing genes from HgCl2.

Evidence for an angiotensin-(1-7) neuropeptidase expressed in the brain medulla and CSF of sheep.

Angiotensin-(1-7) [Ang-(1-7)] is an alternative product of the brain renin-angiotensin system that exhibits central actions to lower blood pressure and improve baroreflex sensitivity. We previously identified a peptidase that metabolizes Ang-(1-7) to the inactive metabolite product Ang-(1-4) in CSF of adult sheep. This study purified the peptidase 1445-fold from sheep brain medulla and characterized this activity. The peptidase was sensitive to the chelating agents o-phenanthroline and EDTA, as well as the mercury compound p-chloromercuribenzoic acid (PCMB). Selective inhibitors to angiotensin-converting enzyme, neprilysin, neurolysin, and thimet oligopeptidase did not attenuate activity; however, the metallopeptidase agent JMV-390 was a potent inhibitor of Ang-(1-7) hydrolysis (Ki = 0.8 nM). Kinetic studies using (125) I-labeled Ang-(1-7), Ang II, and Ang I revealed comparable apparent Km values (2.6, 2.8, and 4.3 µM, respectively), but a higher apparent Vmax for Ang-(1-7) (72 vs. 30 and 6 nmol/min/mg, respectively; p < 0.01). HPLC analysis of the activity confirmed the processing of unlabeled Ang-(1-7) to Ang-(1-4) by the peptidase, but revealed < 5% hydrolysis of Ang II or Ang I, and no hydrolysis of neurotensin, bradykinin or apelin-13. The unique characteristics of the purified neuropeptidase may portend a novel pathway to influence actions of Ang-(1-7) within the brain. Angiotensin-(1-7) actions are mediated by the AT7 /Mas receptor and include reduced blood pressure, decreased oxidative stress, enhanced baroreflex sensitivity, and increased nitric oxide (NO). Ang-(1-7) is directly formed from Ang I by neprilysin (NEP). We identify a new pathway for Ang-(1-7) metabolism in the brain distinct from angiotensin-converting enzyme-dependent hydrolysis. The Ang-(1-7) endopeptidase (A7-EP) degrades the peptide to Ang-(1-4) and may influence central Ang-(1-7) tone.

High quality CdHgTe nanocrystals with strong near-infrared emission: relationship between composition and cytotoxic effects.

High quality CdHgTe quasi core/shell nanocrystals (NCs) were prepared via the one-step method. The relationship between the composition, structure, and property was systematically investigated by the combination of X-ray photoelectron spectroscopy (XPS), inductively coupled plasma atomic emission (ICP), and the photoluminescence (PL) measurements. The quantum yield (QY) was ~50% when the feed ratio of Cd(2+) to Hg(2+) was equal to 1. The PL property was further polished, and the QY was improved to ~80% through the variance of the prepared conditions such as the ratio of ligand to metal ion and HTe(-) to metal ion, pH value, and temperature. In addition, the cytotoxic effects of CdHgTe NCs were systematically studied. The results showed that, for Cd0.21Hg0.79Te NCs, its quasi core/shell structure was very stable and little cadmium ions were released. As a result, such NCs showed little cytotoxicity and would find applications in tissue imaging or detection.

[Recent researches of synthetic mercury sulfide in traditional medicine system].

OBJECTIVE: Herein, the synthesis, component, microstructure and pharmacological and toxicology researches of the Synthetic Mercury Sulfide (S-HgS) a kind of common drug in Chinese, Mongolia, Tibetan medicine, and Indian medicine system were summarized. The similar cognition about mercury toxicity & pharmacological action from some Asian regions was analyzed, and it can supply some useful direction for the traditional Asian medicine system. METHOD: Recent literatures both domestic and abroad were summarized and analyzed. RESULT: S-HgS is the basis of Vermilion, Mongolia-Vermilion, Zuotai, and Ras-sindoor. Athough the processes of synthesis are very different, but the microstructure and pharmacological & toxicology of S-HgS is similar. CONCLUSION: S-HgS has a far-ranging application,and unique curative effect. New technology such as nanotechnology can be used for improving the advancement of traditional Asian medicine.

Role of cinnabar and realgar of WSHFD in protecting against LPS-induced neurotoxicity.

ETHNOPHARMACOLOGICAL RELEVANCE: Wan-Sheng-Hua-Feng-Dan (WSHFD) is a traditional Chinese medicine used for the treatment of neurological disorders. Cinnabar (HgS) and realgar (As(4)S(4)) are included in WSHFD. Are they remedies or poisons? AIM OF STUDY: To investigate the role of cinnabar and realgar in the protective effects of WSHFD on lipopolysaccharide (LPS)-induced neurotoxicity. MATERIALS AND METHODS: Rat primary midbrain neuron-glia cultures were used to explore the effects of WSHFD on LPS-induced dopamine (DA) neurodegeneration. The experiment was randomly divided into control, LPS, LPS+removed (cinnabar and realgar in WSHFD were removed), LPS+reduced (cinnabar and realgar in WSHFD were reduced by 65%) and LPS+original (10% cinnabar and 10% realgar in WSHFD) groups. Dopaminergic neurotoxicity was assessed by [(3)H]DA uptake assay and the quantification of tyrosine hydroxylase (TH)-positive neurons. Microglial activation was evaluated using an anti-OX-42 antibody. The release of intracellular reactive oxygen species (ROS) was quantified via the DCFH-DA probe. The transcripts and production of pro-inflammatory factors were examined by real-time RT-PCR analysis and ELISA, respectively. RESULTS: WSHFD (original) significantly attenuated LPS-induced decrease of DA uptake capacity and TH-positive neuron number, inhibited microglial activation, decreased LPS-induced ROS production, ameliorated LPS-induced elevations of the mRNA expressions of TNFα, iNOS, IL-1ß and COX-2 and the subsequent production of TNFα, NO, IL-1ß and PGE(2) in neuron-glia cultures. However, WSHFD (removed) and (reduced) failed to protect against LPS-induced neurotoxicity. CONCLUSION: Cinnabar and realgar were active ingredients of WSHFD in producing protective effects against LPS-induced neurotoxicity.

In vivo monitoring of organ-selective distribution of CdHgTe/SiO2 nanoparticles in mouse model.

CdHgTe/SiO(2) nanoparticles were prepared by SiO(2) capping on the surface of CdHgTe QDs. The characteristics, such as optical spectra, photostability, size and cell toxicity were investigated. The dynamic distribution of CdHgTe/SiO(2) nanoparticles was in vivo monitored by near infrared fluorescence imaging system. CdHgTe/SiO(2) nanoparticles acted as a novel fluorescence probe have a maximum fluorescence emission of 785 nm and high photo-stability. The hydrodynamic diameter of CdHgTe/SiO(2) nanoparticles could be adjusted to 122.3 nm. Compared to CdHgTe QDs, inhibitory effects of CdHgTe/SiO(2) nanoparticles on proliferation of HCT116 cells decreased to a certain extent. CdHgTe/SiO(2) nanoparticles had their specific dynamic distribution behavior, which provided new perspectives for bio-distribution of nanoparticles.

Mercurius solubilis: actions on macrophages.

BACKGROUND: Macrophages play central roles in homeostasis as well as host defence in innate and acquired immunity, auto-immunity and immunopathology. Our research group has demonstrated the effects of highly diluted toxic substances in macrophages. AIM: To investigate if highly diluted Mercurius solubilis (Merc sol), can activate or modulate macrophage functions. METHODS: We evaluated the effects of Merc sol in the 6, 12, 30 and 200 centesimal high dilutions (CH) potencies on mice peritoneal macrophages (in vitro and in vivo). Merc sol was added to mice's drinking water for 7 days (in vivo treatment) and animals were euthanised and cells were collected. In vitro treatment was performed on macrophages and bone-marrow cell cultures. RESULTS: Macrophages showed activated morphology, both when Merc sol was added directly to the cell culture and to drinking water. The in vitro experiments showed enhanced morphological activation, increased interferon (IFN)γ release in the supernatant at lower dilutions and interleukin (IL)-4 production at higher dilutions. Increase in nitric oxide and decrease in superoxide (O(2)(-)) and hydrogen peroxide (H(2)O(2)) were also observed. In vivo treatment caused a decrease in O(2)(-) and increase in H(2)O(2) production by macrophages. DISCUSSION: Taken together, the results allow us to conclude that highly diluted Merc sol modulates reactive oxygen species (ROS), reactive nitrogen species (RNS) and cytokine secretion, which are central mediators of the immune system, wound healing and body homeostasis.

Effect of Ayurvedic mercury preparation Makaradhwaja on geriatric canine--a preliminary study.

Makaradhwaja, an alchemical Ayurvedic mercury preparation is used as stimulant and vitalizer. Towards veterinary practices, the acceptability, tolerability and toxicity studies were undertaken in geriatric pet dogs aged more than 10 years irrespective of breed and sex for future use. Makaradhwaja (2.5 mg/kg) was used with honey once daily for 30 days. Before and after treatment, blood was collected for hematological studies as well as liver, kidney function and anti-oxidant activity. In control group, honey itself showed no appreciable change whereas, Makaradhwaja lowered neutrophil and total leucocyte count. Serum cholesterol, urea, glucose, alanine amino transferase, aspartate amino transferase, sodium, phosphorus and calcium were decreased. Haemoglobin and serum creatinine were significantly increased. There was appreciable physical, behavioral and body weight change including quality of life. The dose was used in replication of human dose (125 mg/50 kg). Anti-oxidant study showed significant increase of lipid per oxidation in experimental group while the values of ABTS radical cation decolorisation assay although decreased but did not show any significant changes. Decrease of serum urea and increase of serum creatinine could not be explained on single dose response. Different dose study could only explain the optimum dose to be required in canine practices.

Osmosensitivity of transient receptor potential vanilloid 1 is synergistically enhanced by distinct activating stimuli such as temperature and protons.

In animals, body-fluid osmolality is continuously monitored to keep it within a narrow range around a set point (∼300 mOsm/kg). Transient receptor potential vanilloid 1 (TRPV1), a cation channel, has been implicated in body-fluid homeostasis in vivo based on studies with the TRPV1-knockout mouse. However, the response of TRPV1 to hypertonic stimuli has not been demonstrated with heterologous expression systems so far, despite intense efforts by several groups. Thus, the molecular entity of the hypertonic sensor in vivo still remains controversial. Here we found that the full-length form of TRPV1 is sensitive to an osmotic increase exclusively at around body temperature using HEK293 cells stably expressing rat TRPV1. At an ambient temperature of 24°C, a slight increase in the intracellular calcium concentration ([Ca(2+)](i)) was rarely observed in response to hypertonic stimuli. However, the magnitude of the osmosensitive response markedly increased with temperature, peaking at around 36°C. Importantly, the response at 36°C showed a robust increase over a hypertonic range, but a small decrease over a hypotonic range. A TRPV1 antagonist, capsazepine, and a nonspecific TRP channel inhibitor, ruthenium red, completely blocked the increase in [Ca(2+)](i). These results endorse the view that the full-length form of TRPV1 is able to function as a sensor of hypertonic stimuli in vivo. Furthermore, we found that protons and capsaicin likewise synergistically potentiated the response of TRPV1 to hypertonic stimuli. Of note, HgCl(2), which blocks aquaporins and inhibits cell-volume changes, significantly reduced the osmosensitive response. Our findings thus indicate that TRPV1 integrates multiple different types of activating stimuli, and that TRPV1 is sensitive to hypertonic stimuli under physiologically relevant conditions.

Responsiveness of human monocyte-derived dendritic cells to thimerosal and mercury derivatives.

Several cases of skin sensitization have been reported following the application of thimerosal, which is composed of ethyl mercury and thiosalicylic acid (TSA). However, few in vitro studies have been carried out on human dendritic cells (DCs) which play an essential role in the initiation of allergic contact dermatitis. The aim of the present study was to identify the effect of thimerosal and other mercury compounds on human DCs. To address this purpose, DCs derived from monocytes (mono-DCs) were used. Data show that thimerosal and mercury derivatives induced DC activation, as monitored by CD86 and HLA-DR overexpression associated with the secretion of tumor necrosis factor alpha and interleukin 8, similarly to lipopolysaccharide and the sensitizers, 1-chloro-2,4-dinitrobenzene (DNCB) and nickel sulfate, which were used as positive controls. In contrast, TSA, the non-mercury part of thimerosal, as well as dichloronitrobenzene, a DNCB negative control, and the irritant, sodium dodecyl sulfate, had no effect. Moreover, oxidative stress, monitored by ROS induction and depolarization of the mitochondrial membrane potential, was induced by thimerosal and mercury compounds, as well as DNCB, in comparison with hydrogen peroxide, used as a positive control. The role of thiol oxidation in the initiation of mono-DC activation was confirmed by a pre-treatment with N-acetyl-l-cysteine which strongly decreased chemical-induced CD86 overexpression. These data are in agreement with several clinical observations of the high relevance of thimerosal in patch-test reactions and prove that human mono-DCs are useful in vitro tools for determining the allergenic potency of chemicals.