Very high dilutions of dexamethasone inhibit its pharmacological effects in vivo

2001 ◽  
Vol 90 (04) ◽  
pp. 198-203 ◽  
Author(s):  
LV Bonamin ◽  
KS Martinho ◽  
AL Nina ◽  
F Caviglia ◽  
RGW Do Rio

AbstractWe evaluated the interaction of dexamethasone 10−17 and 10−33 M (equivalent to 7cH and 15cH) with dexamethasone in pharmacological concentrations, using as experimental models: acute inflammation induced by carrageenan, Ehrlich ascitic tumour, and migration of tumour infiltrating leukocytes (TIL). Male adult BALB/c mice (n=7 per group) were used in all experiments. Carrageenan (1%) was injected into the footpad for oedema evaluation and into the peritoneal cavity (i.p.), for differential counting of inflammatory cells. Ehrlich ascitic tumour cells (107 viable cells/ml) were injected i.p. and tumour cells were counted after 6 days, by the Trypan blue exclusion method. The differential TIL was counted using smears stained by hematoxylin–eosin. Treatments were made immediately after carrageenan inoculation or once a day, during Ehrlich tumour development, until the animals were killed. Animals were treated with the following preparations: (1) phosphate buffer saline (PBS) solution; (2) dexamethasone (0.5 mg/kg for inflammation model or 4 mg/kg for tumour model) mixed with dexamethasone 7cH or 15cH; (3) dexamethasone (same doses) mixed in PBS. Homeopathic dexamethasone partially blocked the anti-inflammatory effect of pharmacological dexamethasone with regard to paw oedema (two-way ANOVA, P≤0.0008) and polymorphonuclear cell migration (χ2, P=0.0001). No important differences were observed between experimental and control groups, in relation to Ehrlich tumour cells viability or count, or bodyweight, but potentised dexamethasone restored control levels of TIL viability, compared to mice treated with pharmacological doses of dexamethasone (χ2, P≤0.001). The results demonstrate that a potentised substance may change its own pharmacological effects and suggest that ultradilutions effects act mostly on host response.

2021 ◽  
Vol 12 ◽  
Author(s):  
Alessandro Leuti ◽  
Marina Fava ◽  
Niccolò Pellegrini ◽  
Mauro Maccarrone

Inflammation and neuroinflammation are critical mechanisms in the generation of neuropathic pain that is experienced in several chronic diseases. The aberrant inflammation that triggers this pathophysiologic process can be tracked down to an exacerbated immune response, which establishes a vicious cycle and continuously recruits inflammatory cells by inducing chronic tissue damage. Recently, impairment of the cellular and molecular machinery orchestrated by specialized pro-resolving mediators (SPMs)—i.e., endogenous lipids termed resolvins, protectins, maresins, and lipoxins that confine the inflammatory cascades in space and time during the “resolution of inflammation”–has emerged as a crucial event in the derangement of the inflammatory homeostasis and the onset of chronic inflammation and pain. Indeed, a deviant inflammatory response that is not adequately controlled by the resolution network leads to the overproduction of pro-inflammatory eicosanoids that, opposite to SPMs, lead to neuropathic pain. Interestingly, in the last two decades convincing evidence has demonstrated that SPMs antagonize the in vivo activity of pro-inflammatory eicosanoids and, overall, exert potent anti-hyperalgesic effects in a number of pain-associated paradigms of disease, such as arthritis and chemotherapy-induced peripheral neuropathy, as well as in many experimental models of pain like mechanical allodynia, chemical pain, heat hypersensitivity and phase 1 and 2 inflammatory pain. Of note, accumulated evidence supports a synergy between SPMs and other signalling pathways, such as those mediated by transient receptor potential (TRP) channels and those triggered by opioid receptors, suggesting that the cascade of events where inflammation and pain perception take part might be ways more intricated than originally expected. Here, we aim at presenting a state-of-the-art view of SPMs, their metabolism and signalling, in the context of cellular and molecular pathways associated to neuropathic pain.


2021 ◽  
Author(s):  
Aziz UR RAHMAN

Abstract Background: Tumor tissues resist penetration of therapeutic molecules. Multicellular tumor spheroids (MCTSs) were used as an in vitro tumor model. The aim of this study was to determine the growth of MCTSs with the age of spheroids, which could be applied and compared with in vivo drug uptake and penetration. Method: Spheroids were generated by liquid overlay techniques, and their diameter was measured by confocal microscopy for up to two weeks. The trypan blue exclusion method was used to count dead and live cells separately via a hemocytometer. Results: The pentaphysical characteristics of spheroids, including diameter, cell number, volume per cell, viability status, and estimated shell of viable and core of dead cells, were determined. The growth of spheroids was linear over the first week but declined in the 2nd week, which may be due to an overconcentration of dead cells and degraded products inside the spheroids, hence lowering the ratio of live cells in spheroids. Compaction of spheroids occurs from day 3 to day 7, with the mature spheroids having a low amount of extracellular space compared to intracellular volume. Conclusion: Age-oriented growth of MCTSs provides a rationale to predict less rapid penetration as spheroids get older and could be correlated with in vivo tumors to predict pharmaceutical and therapeutic intervention.


Blood ◽  
1975 ◽  
Vol 45 (2) ◽  
pp. 161-170 ◽  
Author(s):  
RA Clark ◽  
SJ Klebanoff ◽  
AB Einstein ◽  
A Fefer

Myeloperoxidase, H2O2, and a halide constitute a potent antimicrobial system. A cytotoxic effect of this system on a line of mouse ascitic lymphoma cells (LSTRA) is demonstrated here using four different assay systems: 51Cr release, trypan blue exclusion, inhibition of glucose C-1 oxidation, and loss of oncogenicity for mice. Deletion of each component of the system, preheating the peroxidase, or addition of azide, cyanide, or catalase abolished the cytotoxicity. Myeloperoxidase was effective with either chloride or iodide as the halide, while lastoperoxidase was effective with iodide but not chloride. The iodinated thyroid hormones, triiodothyronine and thyroxine, could substitute for the halide, and H2O2 could be replaced by a peroxide- generating enzyme system such as glucose and glucose oxidase or by H2O2 producing bacteria such as pneumococci or streptococci. The possibility is raised that the peroxidases of inflammatory cells and certain biologic fluids may affect tumor initiation or growth in vivo.


Homeopathy ◽  
2020 ◽  
Author(s):  
Andreza Pereira dos Santos ◽  
Thayná Neves Cardoso ◽  
Silvia Waisse ◽  
Leoni Villano Bonamin

Abstract Background Complementary and alternative medicine, including homeopathy, is widely used to improve well-being among cancer patients and reduce adverse effects of conventional treatment. In contrast, there are few studies on the use of homeopathic medicines to treat the disease itself. Yet, evidence of possible effectiveness of homeopathic high dilutions in experimental cancer models has been published during the past 20 years. Aim The aim of the study was to perform a systematic review of fundamental research studies on homeopathic high dilutions in cancer. Methods Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline, we conducted a literature search in the database PubMed for original publications, from 2000 to 2018 and in English, on in vitro and in vivo experimental cancer models testing homeopathic high dilutions. Results Twenty-three articles met the inclusion criteria—14 in vitro, eight in vivo, and one in vitro plus in vivo experimental models. Most studies were from India. Research prominently focused on cytotoxic effects involving apoptotic mechanisms. Intrinsic aspects of homeopathy should be considered in experimental designs to emphasize the specificity of such effects. Conclusion Fundamental research of homeopathy in cancer is still at an early stage and has mainly been performed by a few groups of investigators. The results point to an interference of well-selected homeopathic medicines with cell cycle and apoptotic mechanisms in cancer cells. However, these findings still need independent reproduction.


Blood ◽  
1975 ◽  
Vol 45 (2) ◽  
pp. 161-170 ◽  
Author(s):  
RA Clark ◽  
SJ Klebanoff ◽  
AB Einstein ◽  
A Fefer

Abstract Myeloperoxidase, H2O2, and a halide constitute a potent antimicrobial system. A cytotoxic effect of this system on a line of mouse ascitic lymphoma cells (LSTRA) is demonstrated here using four different assay systems: 51Cr release, trypan blue exclusion, inhibition of glucose C-1 oxidation, and loss of oncogenicity for mice. Deletion of each component of the system, preheating the peroxidase, or addition of azide, cyanide, or catalase abolished the cytotoxicity. Myeloperoxidase was effective with either chloride or iodide as the halide, while lastoperoxidase was effective with iodide but not chloride. The iodinated thyroid hormones, triiodothyronine and thyroxine, could substitute for the halide, and H2O2 could be replaced by a peroxide- generating enzyme system such as glucose and glucose oxidase or by H2O2 producing bacteria such as pneumococci or streptococci. The possibility is raised that the peroxidases of inflammatory cells and certain biologic fluids may affect tumor initiation or growth in vivo.


2007 ◽  
Vol 85 (6) ◽  
pp. 621-627 ◽  
Author(s):  
Yan-Hong Li ◽  
Pei-Li Gong

We have previously reported that dauricine protects brain tissues from focal cerebral ischemia. To corroborate this effect, neurotoxicity due to hypoxia and hypoglycemia was assessed in primary cultures of rat cortical neurons by using a trypan blue exclusion method. To further clarify the mechanism, the intracellular Ca2+ concentration ([Ca2+]i) and mitochondrial membrane potential (ΔΨm) of dissociated rat cortical cells were monitored by fura-2 fluorescence measurements and flow cytometry, respectively. The results showed that 1 and 10 μmol/L dauricine significantly enhanced neuronal survival during 4 h of hypoxia and hypoglycemia. Dauricine inhibited the increase in [Ca2+]i and decrease in ΔΨm induced by 30 min of hypoxia and hypoglycemia. When exploring the pathway, we found that 1 μmol/L dauricine inhibited the [Ca2+]i increase induced by 7.5 nmol/L thapsigargin in either the presence or absence of extracellular Ca2+ and by 1 mmol/L l-glutamate in the presence of extracellular Ca2+. These results suggest that dauricine prevents neuronal loss from ischemia in vitro, which is in accordance with our previous research in vivo. In addition, by inhibiting Ca2+ release from the endoplasmic reticulum and Ca2+ influx from the extracellular space, dauricine suppressed the increase in [Ca2+]i and, subsequently, the decrease in ΔΨm induced by hypoxia and hypoglycemia. This effect may underlie the mechanism of action of dauricine on cerebral ischemia.


Author(s):  
José Roberto Pereira Guedes ◽  
Solange Carrasco ◽  
Cláudia Maris Ferreira Mostério ◽  
Leoni Villano Bonamin ◽  
Welluma Souza ◽  
...  

High Dilution is a solution beyond the Avogadro limits that, in the dependence of the applied succussion elicits a suppressive or a stimulant effect on a living cell, with a consequent generation of an oscillatory dose-effect curve. According to Bonamin et al. [1], “Perhaps, the most enigmatic feature regarding the properties of high dilutions is the non-linearity of their effects. In several studies employing in vivo and ex vivo models, especially involving iso-endopathy, an oscillatory potency-effect curve has appeared. The first observations were initially considered as artifacts, but the repetition of this pattern in different studies involving completely different experimental models, in times and places equally different, points out to the existence of a property intrinsic to dynamized systems.” ...


1986 ◽  
Vol 56 (03) ◽  
pp. 318-322 ◽  
Author(s):  
V Diness ◽  
P B Østergaard

SummaryThe neutralization of a low molecular weight heparin (LHN-1) and conventional heparin (CH) by protamine sulfate has been studied in vitro and in vivo. In vitro, the APTT activity of CH was completely neutralized in parallel with the anti-Xa activity. The APTT activity of LHN-1 was almost completely neutralized in a way similar to the APTT activity of CH, whereas the anti-Xa activity of LHN-1 was only partially neutralized.In vivo, CH 3 mg/kg and LHN-1 7.2 mg/kg was given intravenously in rats. The APTT and anti-Xa activities, after neutralization by protamine sulfate in vivo, were similar to the results in vitro. In CH treated rats no haemorrhagic effect in the rat tail bleeding test and no antithrombotic effect in the rat stasis model was found at a protamine sulfate to heparin ratio of about 1, which neutralized APTT and anti-Xa activities. In LHN-1 treated rats the haemorrhagic effect was neutralized when APTT was close to normal whereas higher doses of protamine sulfate were required for neutralization of the antithrombotic effect. This probably reflects the fact that in most experimental models higher doses of heparin are needed to induce bleeding than to prevent thrombus formation. Our results demonstrate that even if complete neutralization of APTT and anti-Xa activities were not seen in LHN-1 treated rats, the in vivo effects of LHN-1 could be neutralized as efficiently as those of conventional heparin. The large fall in blood pressure caused by high doses of protamine sulfate alone was prevented by the prior injection of LHN-1.


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