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1.

Aims

The present study evaluated the carvacrol (CARV) effect on hyperalgesia and nociception induced by sarcoma 180 (S180) in mice.

Main methods

Carvacrol treatment (12.5–50 mg/kg s.c.) once daily for 15 days was started 24 h after injection of the sarcoma cells in the hind paw (s.c.). Mice were evaluated for mechanical sensitivity (von Frey), spontaneous and palpation-induced nociception, limb use and tumor growth on alternate days. CARV effects on the central nervous system were evaluated through immunofluorescence for Fos protein. Molecular docking studies also were performed to evaluate intermolecular interactions of the carvacrol and muscimol, as ligands of interleukin-10 and GABAA receptors.

Key findings

CARV was able to significantly reduce mechanical hyperalgesia and spontaneous and palpation-induced nociception, improve use paw, decrease the number of positively marked neurons in lumbar spinal cord and activate periaqueductal gray, nucleus raphe magnus and locus coeruleus. CARV also caused significant decreased tumor growth. Docking studies showed favorable interaction overlay of the CARV with IL-10 and GABAA.

Significance

Together, these results demonstrated that CARV may be an interesting option for the development of new analgesic drugs for the management of cancer pain.  相似文献   

2.

Aims

β-Adrenoceptors modulate acute wound healing; however, few studies have shown the effects of β-adrenoceptor blockade on chronic wounds. Therefore, this study investigated the effect of β1-/β2-adrenoceptor blockade in wound healing of pressure ulcers.

Main methods

Male mice were daily treated with propranolol (β1-/β2-adrenoceptor antagonist) until euthanasia. One day after the beginning of treatment, two cycles of ischemia–reperfusion by external application of two magnetic plates were performed in skin to induce pressure ulcer formation.

Key findings

Propranolol administration reduced keratinocyte migration, transforming growth factor-β protein expression, re-epithelialization, and necrotic tissue loss. Neutrophil number and neutrophil elastase protein expression were increased in propranolol-treated group when compared with control group. Propranolol administration delayed macrophage mobilization and metalloproteinase-12 protein expression and reduced monocyte chemoattractant protein-1 protein expression. Myofibroblastic differentiation, angiogenesis, and wound closure were delayed in the propranolol-treated animals. Propranolol administration increased neo-epidermis thickness, reduced collagen deposition, and enhanced tenascin-C expression resulting in the formation of an immature and disorganized collagenous scar.

Significance

β1-/β2-Adrenoceptor blockade delays wound healing of ischemia–reperfusion skin injury through the impairment of the re-epithelialization and necrotic tissue loss which compromise wound inflammation, dermal reconstruction, and scar formation.  相似文献   

3.

Aims

Oxaliplatin is a key drug in the treatment of colorectal cancer, but it causes acute and chronic peripheral neuropathies. We previously reported that repeated administration of neurotropin prevents oxaliplatin-induced mechanical allodynia by inhibiting axonal degeneration in rats. In the present study, we investigated the analgesic effect of a single administration of neurotropin on oxaliplatin-induced neuropathy in rats.

Main methods

Oxaliplatin (4 mg/kg) was administered intraperitoneally twice a week for 4 weeks. Cold hyperalgesia was assessed using the acetone test and mechanical allodynia was evaluated using the von Frey test.

Key findings

Repeated injection of oxaliplatin induced cold hyperalgesia on day 5 and mechanical allodynia on day 28. A single administration of neurotropin transiently relieved both pain behaviors. The analgesic effect of neurotropin was inhibited by pretreatment with 5-HT1A, 5-HT2, 5-HT3, and α2 receptor antagonists and by monoamine depletion. Moreover, the analgesic effect of neurotropin was abolished by intrathecal injection of pertussis toxin, a Gi protein inhibitor.

Significance

These results suggest that neurotropin is effective in relieving oxaliplatin-induced neuropathy, and that Gi protein-coupled receptors in the monoaminergic descending pain inhibitory system may be involved in the analgesic effect of neurotropin. Neurotropin may have clinical potential for the treatment of oxaliplatin-induced neuropathies.  相似文献   

4.
5.

Aim

Thymoquinone (TQ), the predominant bioactive constituent of black seed oil (Nigella Sativa), has been shown to possess antineoplastic activity against multifarious tumors. However, the meticulous mechanism of TQ on Akt mediated survival pathway is still unrevealed in breast cancer. Here, we investigated TQ's mechanism of action against PI3K/Akt signaling and its downstream targets by modulating proteins translational machinery, leading to apoptosis in cancer cells.

Main methods

MDA-MB-468 and T-47D cells were treated with TQ and evaluated for its anticancer activity through phase distribution and western blot. Modulatory effects of TQ on Akt were affirmed through kinase and drug potential studies.

Key findings

Studies revealed G1 phase arrest till 24 h incubation with TQ while extended exposure showed phase shift to subG1 indicating apoptosis, supported by suppression of cyclin D1, cyclin E and cyclin dependent kinase inhibitor p27 expression. Immunoblot and membrane potential studies revealed mitochondrial impairment behind apoptotic process with upregulation of Bax, cytoplasmic cytochrome c and procaspase-3, PARP cleavage along with Bcl-2, Bcl-xL and survivin downregulation. Moreover, we construed the rationale behind mitochondrial dysfunction by examining the phosphorylation status of PDK1, PTEN, Akt, c-raf, GSK-3β and Bad in TQ treated cells, thus ratifying the involvement of Akt in apoptosis. Further, the consequential effect of Akt inhibition by TQ is proven by translational repression through deregulated phosphorylation of 4E-BP1, eIF4E, S6R and p70S6K.

Significance

Our observations for the first time may provide a new insight for the development of novel therapies for Akt overexpressed breast cancer by TQ.  相似文献   

6.

Aims

Current no effective therapy is available to halt the progression of Parkinson's disease (PD). Oxidative stress has been implicated in the etiology of PD. The present study evaluates the hypothesis that prevention of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced motor deficits by gastrodin might mainly result from its antioxidant property via interrupting extracellular signal regulated protein kinases (ERK) 1/2-nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway.

Main methods

Pretreatment of mouse model of PD is established by treating C57BL/6 mice with 4 doses of MPTP (30 mg/kg per day, i.p.), with gastrodin (60 mg/kg per day) administered by daily intraperitoneal injection for 2 weeks. Motor behavior of mice was monitored by open-field test and rotarod test. Real-time polymerase chain reaction and Western blotting were used to analyze the expression of genes.

Key findings

MPTP-induced motor deficits were partially and significantly forestalled by gastrodin. Gastrodin treatment prevented MPTP-induced oxidative stress, as measured by malondialdehyde in midbrain. Interestingly, MPTP-intoxicated mice treated with gastrodin robustly increased heme oxygenase 1, superoxide dismutase, glutathione levels, and Nrf2 nuclear translocation in striatum of MPTP-intoxicated mice. Furthermore, results herein suggest that the antioxidant pathway activated by gastrodin involves ERK1/2 phosphorylation.

Significance

Gastrodin protects midbrain of MPTP-intoxicated mice against oxidative stress, in part, through interrupting ERK1/2–Nrf2 pathway mechanism, which will give us an insight into the potential of gastrodin in terms of opening up new therapeutic avenues for PD.  相似文献   

7.

Aims

Although atrial natriuretic peptide has been shown to attenuate ischemia–reperfusion (IR)-induced kidney injury, the effect of natriuretic peptide receptor (NPR)-B activation on IR-induced acute kidney injury is not well documented. The purpose of the present study was to identify the effect of C-type natriuretic peptide (CNP), a selective activator of NPR-B, on the IR-induced acute kidney injury and its mechanisms involved.

Main methods

Unilaterally nephrectomized rats were insulted by IR in their remnant kidney, and they were randomly divided into three groups: sham, vehicle + IR, and CNP + IR groups. CNP (0.2 μg/kg/min) was administered intravenously at the start of a 45-min renal ischemia for 2 h. Rats were then killed 24 h after I/R, and the blood and tissue samples were collected to assess renal function, histology, TUNEL assay, and Western blot analysis of kidney Bax and Bcl-2 expressions.

Key findings

The levels of blood urea nitrogen and serum creatinine were significantly increased in rats after IR compared with vehicle-treated rats. IR elevated apoptosis, Bcl-2/Bax ratio, TUNEL positivity, oxidative stress parameters, malondialdehyde concentration, and superoxide dismutase activity. IR also induced epithelial desquamation of the proximal tubules and glomerular shrinkage. CNP significantly attenuated the IR-induced increase in BUN and serum creatinine. Furthermore, CNP restored the suppressed renal cyclic guanosine 3′ 5′-monophosphate levels caused by IR insult.

Significance

Study findings suggest that CNP could ameliorate IR-induced acute kidney injury through inhibition of apoptotic and oxidative stress pathways, possibly through NPR-B-cGMP signaling.  相似文献   

8.
9.

Background

Diallyl disulfide (DADS) is a garlic-derived organosulfur compound. The current study is designed to evaluate the protective effects of DADS against ethanol-induced oxidative stress, and to explore the underlying mechanisms by examining the HO-1/Nrf-2 pathway.

Methods

We investigated whether or not DADS could activate the HO-1 in normal human liver cell LO2, and then evaluated the protective effects of DADS against ethanol-induced damage in LO2 cells and in acute ethanol-intoxicated mice. The biochemical parameters were measured using commercial kits. HO-1 mRNA level was determined by RT-PCR. Histopathology and immunofluorescence assay were performed with routine methods. Protein levels were measured by western blot.

Results

DADS significantly increased the mRNA and protein levels of HO-1, stimulated the nuclear translocation of Nrf-2 and increased the phosphorylation of MAPK in LO2 cells. The nuclear translocation of Nrf-2 was abrogated by MAPK inhibitors. DADS significantly suppressed ethanol-induced elevation of lactate dehydrogenase (LDH) and aspartate transaminase (AST) activities, decrease of glutathione (GSH) level, increase of malondialdehyde (MDA) levels, and apoptosis of LO2 cells, which were all blocked by ZnPPIX. In mice, DADS effectively suppressed acute ethanol-induced elevation of aminotransferase activities, and improved liver histopathological changes, which might be associated with HO-1 activation.

Conclusion

These results demonstrate that DADS could induce the activation of HO-1/Nrf-2 pathway, which may contribute to the protective effects of DADS against ethanol-induced liver injury.

General significance

DADS may be beneficial for the prevention and treatment of ALD due to significant activation of HO-1/Nrf-2 pathway.  相似文献   

10.

Aims

Two natural alkaloids, methyl (M) and isopropyl (I) N-methylanthranilates, with recently demonstrated significant pharmacological activities, were assayed for their possible overall effect on intact gastric mucosa and their protective properties towards the onset of gastric lesions induced by diclofenac (a non-steroidal anti-inflammatory drug, NSAID) or ethanol.

Main methods

The influence of I and M on gastric mucosa integrity was assessed by oral administration in doses of 200 mg/kg. The gastroprotective action of I and M in doses of 50, 100 and 200 mg/kg was analyzed in the diclofenac and ethanol-induced gastric lesion models in rats. After the treatment, the stomachs of the animals were analyzed (captured by a digital camera). Ulcer scoring, morphometric and histopathological analyses of the stomachs were done.

Key findings

The oral application of these compounds on their own, even in quite high doses (200 mg/kg) did not induce gastric lesions. Both alkaloids exerted a very strong antiulcer activity, even in low doses (50 mg/kg), by decreasing the number of lesions caused by the application of either diclofenac or ethanol, eliminating them completely or reducing them to a form of mucosal hyperemia.

Significance

Their possible mechanism of action was discussed and due to their many positive properties including anxiolytic, antidepressant, antinociceptive, anti-inflammatory and gastroprotective activities, as well as a cheap and simple synthetic route for their preparation, methyl and isopropyl N-methylanthranilates, both alike, might represent a cost effective alternative sought for in the treatment of peptic ulcers and/or new safer NSAIDs for pain management.  相似文献   

11.

Background

The abasic sites represent one of the most frequent lesions of DNA and most of the events able to generate such modifications involve guanine bases. G-rich sequences are able to form quadruplex structures that have been proved to be involved in several important biological processes.

Methods

In this paper, we report investigations, based on calorimetric, UV, CD and electrophoretic techniques, on 12 oligodeoxynucleotides analogues of the quadruplex forming human telomere sequence d[TA(G3T2A)3G3], in which each guanine has been replaced, one at a time, by an abasic site mimic.

Results

Although all data show that the modified sequences preserve their ability to form quadruplex structures, the thermodynamic parameters clearly indicate that the presence of an abasic site decreases their thermal stability compared to the parent unmodified sequence, particularly if the replacement concerns one of the guanosines involved in the formation of the central G-tetrad.

Conclusions

The collected data indicate that the effects of the presence of abasic site lesions in telomeric quadruplex structures are site-specific. The most dramatic consequences come out when this lesion involves a guanosine in the centre of a G-run.

General significance

Abasic sites, by facilitating the G-quadruplex disruption, could favour the formation of the telomerase primer. Furthermore they could have implications in the pharmacological approach targeting telomere.  相似文献   

12.

Background

In a previous study, we deleted three aldehyde dehydrogenase (ALDH) genes, involved in ethanol metabolism, from yeast Saccharomyces cerevisiae and found that the triple deleted yeast strain did not grow on ethanol as sole carbon source. The ALDHs were NADP dependent cytosolic ALDH1, NAD dependent mitochondrial ALDH2 and NAD/NADP dependent mitochondrial ALDH5. Double deleted strain ΔALDH2+ΔALDH5 or ΔALDH1+ΔALDH5 could grow on ethanol. However, the double deleted strain ΔALDH1+ΔALDH2 did not grow in ethanol.

Methods

Triple deleted yeast strain was used. Mitochondrial NAD dependent ALDH from yeast or human was placed in yeast cytosol.

Results

In the present study we found that a mutant form of cytoplasmic ALDH1 with very low activity barely supported the growth of the triple deleted strain (ΔALDH1+ΔALDH2+ΔALDH5) on ethanol. Finding the importance of NADP dependent ALDH1 on the growth of the strain on ethanol we examined if NAD dependent mitochondrial ALDH2 either from yeast or human would be able to support the growth of the triple deleted strain on ethanol if the mitochondrial form was placed in cytosol. We found that the NAD dependent mitochondrial ALDH2 from yeast or human was active in cytosol and supported the growth of the triple deleted strain on ethanol.

Conclusion

This study showed that coenzyme preference of ALDH is not critical in cytosol of yeast for the growth on ethanol.

General significance

The present study provides a basis to understand the coenzyme preference of ALDH in ethanol metabolism in yeast.  相似文献   

13.
A mutant of Mycobacterium smegmatis is a potential class I model substitute for Mycobacterium tuberculosis. Because not all of the rifamycins have been tested in this organism, we determined bactericidal profiles for the 6 major rifamycin derivatives. The profiles closely mirrored those established for M. tuberculosis. Rifalazil was confirmed to be the most potent rifamycin. Because the tuberculous granuloma presents a harshly oxidizing environment we explored the effects of oxidation on rifamycins. Mass spectrometry confirmed that three of the six major rifamycins showed autoxidation in the presence of trace metals. Oxidation could be monitored by distinctive changes including isosbestic points in the ultraviolet–visible spectrum. Oxidation of rifamycins abrogated anti-mycobacterial activity in M. smegmatis. Protection from autoxidation was conferred by binding susceptible rifamycins to tear lipocalin, a promiscuous lipophilic protein. Rifalazil was not susceptible to autoxidation but was insoluble in aqueous solution. Solubility was enhanced when complexed to tear lipocalin and was accompanied by a spectral red shift. The positive solvatochromism was consistent with robust molecular interaction and binding. Other rifamycins also formed a complex with lipocalin, albeit to a lesser extent. Protection from oxidation and enhancement of solubility with protein binding may have implications for delivery of select rifamycin derivatives.  相似文献   

14.

Background

Excessive melanin production and accumulation are characteristics of a large number of skin diseases, including melasma, and post-inflammatory hyperpigmentation. During our on-going search for new agents with an inhibitory effect on tyrosinase, we synthesized a new type of tyrosinase inhibitor, 4-(thiazolidin-2-yl)benzene-1,2-diol (MHY-794), which directly inhibits mushroom tyrosinase.

Methods

The inhibitory effect of MHY-794 on tyrosinase activity and nitric oxide (NO) scavenging activity was evaluated in cell free system. Additional experiments were performed using B16F10 melanoma cells to demonstrate the effects of MHY-794 in vitro. HRM2 hairless mice were used to evaluate anti-melanogenic effects of MHY-794 in vivo.

Results

MHY-794 effectively inhibited mushroom tyrosinase activity in cell free system. In silico docking simulation also supported the inhibitory effects of MHY-794 on mushroom tyrosinase. MHY-794 also proved to be effective at scavenging nitric oxide (NO), which serves as an important modulator in the melanogenesis signaling pathway. In addition, MHY-794 effectively inhibited SNP (NO donor)-induced melanogenesis by directly inhibiting tyrosinase and diminishing NO-mediated melanogenesis signaling in B16 melanoma cells. The anti-melanogenic effects of MHY-794 were further confirmed in HRM2 hairless mice. Ultraviolet light (UV) significantly up-regulated NO-mediated melanogenesis signaling in HRM2 hairless mice, but MHY-794 effectively inhibited both melanogenesis and diminished UV-induced NO-signaling.

Conclusions

Our results indicate that MHY-794 is highly effective at inhibiting NO-mediated melanogenesis in vitro and in vivo by direct NO scavenging and directly inhibiting tyrosinase activity, and suggest that MHY-794 be considered a new developmental candidate for the treatment of hyper-pigmentation disorders.

General significance

MHY-794, which showed great efficacy on NO-mediated melanogenesis by direct NO scavenging as well as direct inhibition of tyrosinase catalytic activity, might be utilized for the development of a new candidate for treatment of the hyper-pigmentation disorders.  相似文献   

15.

Background

The main objective of the present study was to investigate chemical composition and possible cyto/genotoxic potential of several medical implant materials commonly used in total hip joint replacement.

Methods

Medical implant metal alloy (Ti6Al4V and CoCrMo) and high density polyethylene particles were analyzed by energy dispersive X-ray spectrometry while toxicological characterization was done on human lymphocytes using multi-biomarker approach.

Results

Energy dispersive X-ray spectrometry showed that none of the elements identified deviate from the chemical composition defined by appropriate ISO standard. Toxicological characterization showed that the tested materials were non-cyto/genotoxic as determined by the comet and cytokinesis-block micronucleus (CBMN) assay. Particle morphology was found (by using scanning electron and optical microscope) as flat, sharp-edged, irregularly shaped fiber-like grains with the mean particle size less than 10 µm; this corresponds to the so-called "submicron wear". The very large surface area per wear volume enables high reactivity with surrounding media and cellular elements.

Conclusions

Although orthopedic implants proved to be non-cyto/genotoxic, in tested concentration (10 μg/ml) there is a constant need for monitoring of patients that have implanted artificial hips or other joints, to minimize the risks of any unwanted health effects.

General significance

The fractal and multifractal analyses, performed in order to evaluate the degree of particle shape effect, showed that the fractal and multifractal terms are related to the "remnant" level of the particles' toxicity especially with the cell viability (trypan blue method) and total number of nucleoplasmic bridges and nuclear buds as CBMN assay parameters.  相似文献   

16.

Aims

Acute ethanol intoxication (AEI) attenuates the arginine vasopressin (AVP) response to hemorrhage leading to impaired hemodynamic counter-regulation and accentuated hemodynamic stability. Previously we identified that the ethanol-induced impairment of circulating AVP concentrations in response to hemorrhage was the result of augmented central nitric oxide (NO) inhibition. The aim of the current study was to examine the mechanisms underlying ethanol-induced up-regulation of paraventricular nucleus (PVN) NO concentration. Angiotensin (ANG) (1-7) is an important mediator of NO production through activation of the Mas receptor. We hypothesized that Mas receptor inhibition would decrease central NO concentration and thus restore the rise in circulating AVP levels during hemorrhagic shock in AEI rats.

Main methods

Conscious male Sprague–Dawley rats (300–325 g) received a 15 h intra-gastric infusion of ethanol (2.5 g/kg + 300 mg/kg/h) or dextrose prior to a fixed-pressure (~ 40 mm Hg) 60 min hemorrhage. The Mas receptor antagonist A-779 was injected through an intracerebroventricular (ICV) cannula 15 min prior to hemorrhage.

Key findings

PVN NOS activity and NO were significantly higher in AEI compared to DEX-treated controls at the completion of hemorrhage. ICV A-779 administration decreased NOS activity and NO concentration, partially restoring the rise in circulating AVP level at completion of hemorrhage in AEI rats.

Significance

These results suggest that Mas receptor activation contributes to the NO-mediated inhibitory tone of AVP release in the ethanol-intoxicated hemorrhaged host.  相似文献   

17.
18.
19.

Background

The Galanthus nivalis agglutinin (GNA)-related lectins have been reported to bear antiproliferative and apoptosis-inducing activities in cancer cells; however, the precise mechanisms by which GNA-related lectins induce cell death are still only rudimentarily understood.

Methods

In the present study, Polygonatum odoratum lectin (designated POL), a mannose-binding specific GNA-related lectin, possessed a remarkable antiproliferative activity toward murine fibrosarcoma L929 cells. And, this lectin induced L929 cell apoptosis in a caspase-dependent manner. In addition, POL treatment increased the levels of FasL and Fas-Associated protein with Death Domain (FADD) proteins and resulted in caspase-8 activation. Also, POL treatment caused mitochondrial transmembrane potential collapse and cytochrome c release, leading to activations of caspase-9 and caspase-3. Moreover, POL treatment enhanced tumor necrosis factor α (TNFα)-induced L929 cell apoptosis.

Results

Our data demonstrate for the first time that this lectin induces apoptosis through both death-receptor and mitochondrial pathways, as well as amplifies TNFα-induced L929 cell apoptosis.

General significance

These inspiring findings would provide new molecular basis for further understanding cell death mechanisms of the Galanthus nivalis agglutinin (GNA)-related lectins in future cancer investigations.  相似文献   

20.

Purpose

To describe at molecular level a family with pulverulent congenital cataract associated with a CRYGC gene mutation.

Methods

One family with several affected members with pulverulent congenital cataract and 230 healthy controls were examined. Genomic DNA from leukocytes was isolated to analyze the CRYGA-D cluster, CX46, CX50 and MIP genes through high-resolution melting curve and DNA sequencing.

Results

DNA sequencing in the affected members revealed the c.143G>A mutation (p.R48H) in exon 2 of the CRYGC gene; 230 healthy controls and ten healthy relatives were also analyzed and none of them showed the c.143G>A mutation. No other polymorphisms or mutations were found to be present.

Conclusion

In the present study, we described a family with pulverulent congenital cataract that segregated the c.143G>A mutation (p.R48H) in the CRYGC gene. A few mutations have been described in the CRYGC gene in autosomal dominant cataract, none of them with pulverulent cataract making clear the clinical heterogeneity of congenital cataract. This mutation has been associated with the phenotype of congenital cataract but also is considered an SNP in the NCBI data base. Our data and previous report suggest that p.R48H could be a disease-causing mutation and not an SNP.  相似文献   

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