Astragali radix: could it be an adjuvant for oxaliplatin-induced neuropathy?

Neurotoxicity is a major side effect of platinum derivatives both during and after treatment. In the absence of effective pharmacological compounds, the opportunity to identify safe adjuvant treatments among medicinal plants seems appropriate. Astragali radix is an adaptogenic herbal product recently analyzed in platinum-treated cancer patients. With the aim of evaluating the anti-neuropathic profile of Astragali radix, a previously characterized aqueous (Aqu) and two hydroalcoholic (20%HA and 50%HA) extracts were tested in a rat model of oxaliplatin-induced neuropathy. Repeated administrations significantly reduced oxaliplatin-dependent hypersensitivity with 50%HA, the most effective, fully preventing mechanical and thermal hypersensitivity. Ex vivo, 50%HA reduced morphometric and molecular alterations induced by oxaliplatin in peripheral nerve and dorsal-root-ganglia. In the spinal cord and in brain areas, 50%HA significantly decreased activation of microglia and astrocytes. Furthermore, 50%HA prevented the nephro- and hepato-toxicity induced by the anticancer drug. The protective effect of 50%HA did not alter oxaliplatin-induced apoptosis in colon tumors of Pirc rats, an Apc-driven model of colon carcinogenesis. The hydroalcoholic extract (50%HA) of Astragali radix relieves pain and promotes the rescue mechanisms that protect nervous tissue from the damages triggering chronic pain. A safe profile strongly suggests the usefulness of this natural product in oxaliplatin-induced neuropathy.

Effect of the SOD mimetic MnL4 on in vitro and in vivo oxaliplatin toxicity: Possible aid in chemotherapy induced neuropathy.

BACKGROUND: One of the most discomfortable dose-limiting adverse reactions of effective drugs for the treatment of solid tumors is a peripheral neuropathy which is the main reason for dose reduction and discontinuation of the therapy. We identified oxidative stress as one target of oxaliplatin toxicity in the search of possible adjuvant therapies to prevent neuropathy and alleviate pain. Therefore, we studied an effective SOD mimetic compound, MnL4, as a possible adjuvant treatment in in vitro cellular cultures and in vivo on a rat model of oxaliplatin-induced neuropathy. METHODS AND RESULTS: All rat manipulations were carried out according to the European Community guidelines for animal care. We performed experiments on SH-SY5Y, HT-29 and primary cortical rat astrocytes. Incubation with 100 µM oxaliplatin increased superoxide anion production and caspase 3/7 activity in the neuronal cell line SH-SY5Y and cortical astrocytes. MnL4 (10 µM) significantly reduced the increase in superoxide anion in both cell types, but prevented caspase 3/7 activity only in astrocytes. MnL4 reduced lipid peroxidation induced by oxaliplatin and normalized the intracellular calcium signal evoked by ATP and acetylcholine in astrocytes, preincubated with oxaliplatin. MnL4 did not interfere with the concentration- and time-dependent cytotoxic effects of oxaliplatin on the cancer cell lines HT-29 and LoVo. In vivo MnL4 reduced the response at mechanical noxious and mechanical and thermal non-noxious stimuli in oxaliplatin treated animals. Rat rota-rod performances were improved. CONCLUSION: Since MnL4 exerts its beneficial effects without interfering with the anticancer activity of oxaliplatin, it could be proposed as adjuvant to prevent and reduce oxaliplatin induced neuropathy.

Management of chronic pruritus with a UV filtering topical cream.

Chronic pruritus is a common dermatological condition affecting 10-13% of the general population. UVB phototherapy has been demonstrated to be effective in relieving the symptoms of pruritus. However, phototherapy is rarely administered because the treatment is time-consuming and expensive, when compared to other topical drugs. In previous works, it has been reported that a topical cream, which selectively filters solar UVB can be used as a convenient alternative to traditional phototherapy. Here, we report the results of a pilot study aimed at assessing the effectiveness of the cream for treating pruritus. Seven patients with pruritus symptoms were included in the study. After 3 months of treatment (3 sessions per week), all patients noted improvement in pruritus symptoms. These preliminary results demonstrate that the novel topical cream could provide a convenient, low cost treatment for chronic pruritus patients.

Widespread pain reliever profile of a flower extract of Tanacetum parthenium.

BACKGROUND: Tanacetum parthenium L., commonly called Feverfew, is known for anti-inflammatory and anti-migraine properties. PURPOSE: Aimed to individuate new therapeutical strategies to control acute and persistent pain induced by different origins we tested two hydroalcoholic extracts obtained from Feverfew flowers and leaves, respectively. STUDY DESIGN: Extracts were characterized according to the European Pharmacopoeia monograph. Both the extracts were tested after acute per os administration in the dose range 30-1000 mg kg(-1). The anti-nociceptive properties were evaluated by the Writhing test in mice. RESULTS: The number of abdominal contractions was dose dependently reduced by the flower extract. It reduced mechanical hypersensitivity (Paw pressure test) related to the acute inflammatory phase induced by carrageenan similarly to diclofenac and ibuprofen. In the osteoarthritis model induced by intra articular injection of monoiodoacetate (MIA) the flower extract significantly increased the pain threshold peaking 30 min after treatment. Moreover, it was effective in the chronic constriction injury model of neuropathic pain showing activity similar to the anti-epileptic drug gabapentin. The flower extract activity was confirmed in rat models of chemotherapy-induced neuropathic pain. The mechanical hypersensitivity induced by repeated treatments with the anticancer drug oxaliplatin and with the antiviral dideoxycytidine was significantly reduced after a single injection of Feverfew flower extract. The leaf extract showed lesser efficacy and potency and it was devoid of any effect in carrageenan-, MIA- and chemotherapy-induced pain. CONCLUSION: The present Feverfew flower extract behaves as a potent pain reliever in acute, inflammatory, articular and neuropathic pain. It appears as a natural strategy potentially suitable for the treatment of different kinds of pain.

In Vitro Evidence for the Use of Astragali Radix Extracts as Adjuvant against Oxaliplatin-Induced Neurotoxicity.

The repeated exposure to the anticancer drug oxaliplatin induces a disabling, painful neuropathy. The current pharmacological treatments are unsatisfactory and unable to modify the complex nervous damage induced by the platin derivative. Recently, we described a system of cellular measures of oxidative stress as a method for studying features of oxaliplatin neurotoxicity and screening new compounds able to reduce oxaliplatin-induced neuropathy. Based on this experimental design, the protective properties of Astragali radix were studied comparing aqueous and two hydroalcoholic root extracts. Aqueous and the 20 % hydroalcoholic (20 % water) extract were prepared from plant material, while the 50 % hydroalcoholic (50 % water) extract was a commercial one. All of the extracts were characterized in terms of drug extract ratio and content of typical isoflavonoids, Astragaloside IV, and related saponins. Furthermore, the molecular weight of the polysaccharide fraction was evaluated by light scattering analysis. Oxaliplatin increased the superoxide anion production both in the neuronal-derived cell line SH-SY5Y and in primary cultures of rat cortical astrocytes. Aqueous and the 50 % hydroalcoholic extract (50 µg/mL) showed significant antioxidant effects. In astrocytes, aqueous and the 50 % hydroalcoholic extract showed protective effects against oxaliplatin-induced lipid peroxidation (malonyl dialdehyde levels), protein (carbonylated proteins), and DNA oxidation (8-OH-2-dG levels). The 50 % hydroalcoholic extract was the most active in preventing the activation of the apoptotic enzyme caspase-3 and it was the only able to stimulate astrocyte viability. None of the tested extracts interfered with the toxicity elicited by oxaliplatin in the human colon adenocarcinoma cell line HT-29. The pharmacological profile of Astragali radix extracts, in particular, the aqueous and 50 % hydroalcoholic extracts, makes these natural products candidates as therapeutic adjuvant agents against oxaliplatin neurotoxicity.

A smart platform for hyperthermia application in cancer treatment: cobalt-doped ferrite nanoparticles mineralized in human ferritin cages.

Magnetic nanoparticles, MNPs, mineralized within a human ferritin protein cage, HFt, can represent an appealing platform to realize smart therapeutic agents for cancer treatment by drug delivery and magnetic fluid hyperthermia, MFH. However, the constraint imposed by the inner diameter of the protein shell (ca. 8 nm) prevents its use as heat mediator in MFH when the MNPs comprise pure iron oxide. In this contribution, we demonstrate how this limitation can be overcome through the controlled doping of the core with small amount of Co(II). Highly monodisperse doped iron oxide NPs with average size of 7 nm are mineralized inside a genetically modified variant of HFt, carrying several copies of α-melanocyte-stimulating hormone peptide, which has already been demonstrated to have excellent targeting properties toward melanoma cells. HFt is also conjugated to poly(ethylene glycol) molecules to increase its in vivo stability. The investigation of hyperthermic properties of HFt-NPs shows that a Co doping of 5% is enough to strongly enhance the magnetic anisotropy and thus the hyperthermic efficiency with respect to the undoped sample. In vitro tests performed on B16 melanoma cell line demonstrate a strong reduction of the cell viability after treatment with Co doped HFt-NPs and exposure to the alternating magnetic field. Clear indications of an advanced stage of apoptotic process is also observed from immunocytochemistry analysis. The obtained data suggest this system represents a promising candidate for the development of a protein-based theranostic nanoplatform.

Involvement of α7 nAChR subtype in rat oxaliplatin-induced neuropathy: effects of selective activation.

Oxaliplatin, unlike other platinum anticancer agents, has only mild toxic effects on the hematopoietic, urinary and gastrointestinal systems. Its dose-limiting side effect is neurotoxicity that may evolve to a neuropathic syndrome which is difficult to treat. In this study we treated rats with oxaliplatin (2.4 mg/kg/day intraperitoneally, for 3 weeks), and observed that expression levels of the α7 nicotinic acetylcholine receptor (nAChR) subunit were dramatically decreased both in the peripheral and central nervous system. The repeated administration (30 mg/kg/day per os, for 3 weeks) of (R)-ICH3, the most active enantiomer of a novel α7 nAChR agonist, and of PNU-282987 prevented the receptor down-regulation. On the other hand, both agonists per se up-regulated the α7 nAChR subunit compared to control. (R)-ICH3 and PNU-282987 significantly reduced oxaliplatin-dependent alterations of the pain threshold when noxious or non-noxious stimuli were used. Further ex vivo analysis highlighted their neuroprotective effects in dorsal root ganglia and peripheral nerves. The two agonists did not prevent the increase in microglia cell number induced by oxaliplatin in the central nervous system. Astrocyte density was enhanced by the agonist treatment in the spinal cord, thalamus and somatosensory area 1 as opposed to the effects of oxaliplatin treatment. (R)-ICH3 and PNU-282987 per se increased glial cell number in a region-specific manner. In summary, α7 nAChR is involved in oxaliplatin-dependent neuropathology and the agonists (R)-ICH3 and PNU-282987 reduce pain and protect nervous tissue with concomitant glial activation. Since glial cells play a role both in pain and in neuroprotection, an α7 AChR-dependent modulation of glial functions is suggested to distinguish rescue signals from the pathological pain-mediating pathway.