Antinociceptive Effect of a p-Cymene/ß-Cyclodextrin Inclusion Complex in a Murine Cancer Pain Model: Characterization Aided through a Docking Study.

Pain is one of the most prevalent and difficult to manage symptoms in cancer patients, and conventional drugs present a range of adverse reactions. The development of ß-cyclodextrins (ß-CD) complexes has been used to avoid physicochemical and pharmacological limitations due to the lipophilicity of compounds such as p-Cymene (PC), a monoterpene with antinociceptive effects. Our aim was to obtain, characterize, and measure the effect of the complex of p-cymene and ß-cyclodextrin (PC/ß-CD) in a cancer pain model. Initially, molecular docking was performed to predict the viability of complex formation. Afterward, PC/ß-CD was obtained by slurry complexation, characterized by HPLC and NMR. Finally, PC/ß-CD was tested in a Sarcoma 180 (S180)-induced pain model. Molecular docking indicated that the occurrence of interaction between PC and ß-CD is favorable. PC/ß-CD showed complexation efficiency of 82.61%, and NMR demonstrated PC complexation in the ß-CD cavity. In the S180 cancer pain model, PC/ß-CD significantly reduced the mechanical hyperalgesia, spontaneous nociception, and nociception induced by non-noxious palpation at the doses tested (p < 0.05) when compared to vehicle differently from free PC (p > 0.05). Therefore, the complexation of PC in ß-CD was shown to improve the pharmacological effect of the drug as well as reducing the required dose.

γ-Terpinene complexed with ß-cyclodextrin attenuates spinal neuroactivity in animals with cancer pain by Ca2+ channel block.

OBJECTIVES: Considering that γ-terpinene (γ-TPN) is a monoterpene found in Cannabis oil, with high lipophilicity and limited pharmacokinetics, our objective was to evaluate whether its complexation in ß-cyclodextrin (γ-TPN/ß-CD) could improve its physicochemical properties and action on cancer pain, as well as verify the mechanisms of action involved. METHODS: The γ-TPN/ß-CD was prepared and submitted to physicochemical characterization. Animals with sarcoma 180 were treated (vehicle, γ-TPN 50 mg/kg, γ-TPN/ß-CD 5 mg/kg or morphine) and assessed for hyperalgesia, TNF-α and IL-1ß levels, iNOS and c-Fos activity. The effects of γ-TPN on calcium channels were studied by patch-clamp and molecular docking. RESULTS: ß-CD improved the physicochemical properties and prolonged the anti-hyperalgesic effect of γ-TPN. This compound also reduced the levels of IL-1ß, TNF-α and iNOS in the tumour, and c-Fos protein in the spinal cord. In addition, it reduced Ca2+ current, presenting favourable chemical interactions with different voltage-dependent calcium channels. CONCLUSION: These results indicate that the complexation of γ-TPN into ß-CD increases its stability and time effect, reducing spinal neuroactivity and inflammation by blocking calcium channels.

Limonene, a citrus monoterpene, non-complexed and complexed with hydroxypropyl-ß-cyclodextrin attenuates acute and chronic orofacial nociception in rodents: Evidence for involvement of the PKA and PKC pathway.

BACKGROUND: Chronic orofacial pain is a serious public health problem with a prevalence of 7-11% in the population. This disorder has different etiologies and characteristics that make pharmacological treatment difficult. Natural products have been shown to be a promising source of treatments for the management of chronic pain, as an example the terpenes. PURPOSE: The aim of this study was to evaluate the anti-nociceptive and anti-inflammatory effects of one of these terpenes, d-limonene (LIM - a common monoterpene found in citrus fruits) alone and complexed with hydroxypropyl-ß-cyclodextrin (LIM/HPßCD) in preclinical animal models. METHODS: Orofacial pain was induced by the administration of hypertonic saline on the corneal surface, the injection of formalin into the temporomandibular joint (TMJ), or chronic constriction injury of the infraorbital nerve (CCI-IoN). The study used male Wistar rats and Swiss mice treated with LIM (50 mg/kg), LIM/HPßCD (50 mg/kg), vehicle (control), gabapentin or morphine, and eyes wiping (induced by hypertonic saline), face rubbing (formalin-induced in TMJ) or mechanical hyperalgesia (provoked by CCI-IoN) were assessed. Additionally, ELISA was used to measure TNF-α, and western blot analysis to assess levels of PKAcα, NFκB, p38MAPK and phosphorylated PKC substrates. Serum levels of aspartate aminotransferase (AST) and alanine transferase (ALT) were also evaluated. RESULTS: LIM and LIM/HPßCD significantly reduced (p < 0.001) corneal nociception and formalin-induced TMJ nociception. In addition, both substances attenuated (p < 0.001) mechanical hyperalgesia in the CCI-IoN model. The antinociceptive effect induced by LIM and HPßCD/LIM was associated with decreased TNF-α levels, downregulation of the NFκB and p38MAPK signalling pathways and reduced PKC substrate phosphorylation and PKA immunocontent. Moreover, the results demonstrated that complexation with HPßCD was able to decrease the therapeutic dose of LIM. CONCLUSION: LIM was found to be a promising molecule for the treatment of orofacial pain due to its capacity to modulate some important mediators essential to the establishment of pain, and HPßCD can be a key tool to improve the profile of LIM.

Anti-obesity properties and mechanism of action of flavonoids: A review.

Obesity is a major public health problem, and there is increasing scientific interest in its mechanisms, as well as a search for new compounds with antioxidant and anti-inflammatory properties that can minimize the metabolic complications associated with its pathology. One potential source of these compounds is natural products; Among these, flavonoids are a promising group of natural substances. Flavonoids are active constituents with diverse biological activities and are widely found in plants kingdom. Numerous studies have shown that flavonoids can effectively inhibit obesity and related metabolic disorders. The review synthesizes recent evidence in respect of progress in the understanding of the anti-obesity effects of flavonoids. Such effects which occurs through the modulation of proteins, genes and transcriptional factors involved in decreasing lipogenesis, increasing lipolysis, expenditure energy, stimulating fatty acids B-oxidation, digestion and metabolism of carbohydrates. In addition to mitigating inflammatory responses and suppress oxidative stress. A better understanding of the modulating effects and mechanisms of flavonoids in relation to obesity will allow us to better use these compounds to treat or even prevent obesity and its associated comorbidities.

Resistance training increases insulin-induced vasodilation in the mesenteric artery of healthy rats.

This study evaluated the ability of resistance training (RT) of moderate intensity to promote vascular changes in insulin-induced vasodilation in healthy animals. Wistar rats were divided into two groups: control (CON) and trained (eight weeks of training, performing 3 sets with 10 repetitions at 60% of maximum intensity). Forty-eight hours after the last session of the RT, the animals were sacrificed and vascular reactivity to insulin in the absence and presence of LY294002 (phosphatidylinositol 3-kinase inhibitors (PI3K), L-NAME (nitric oxide synthase (NOS) inhibitors) and BQ123 (endothelin A antagonist (ET-A) receptor). In addition, phenylephrine (Phe)-induced vasoconstriction in the absence and presence of L-NAME was also evaluated. The RT group showed greater vasodilation in maximal response compared to the CON group. After PI3K inhibition, vasodilation was reduced in both groups. However, when the NOS participation was evaluated, the RT group showed contraction in relation to the CON group, which was abolished by BQ123. In addition, the RT group had an increase in nitrite levels compared to the CON group. When the Phe response was evaluated, there was a reduction in tension in the RT group compared to the CON group. The results suggest that RT improves vascular reactivity.

Wound healing properties of flavonoids: A systematic review highlighting the mechanisms of action.

BACKGROUND: Flavonoids are a class of compounds with a wide variety of biological functions, being an important source of new products with pharmaceutical potential, including treatment of skin wounds. PURPOSE: This review aimed to summarize and evaluate the evidence in the literature in respect of the healing properties of flavonoids on skin wounds in animal models. STUDY DESIGN: This is a systematic review following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. METHODS: This was carried out through a specialized search of four databases: PubMed, Scopus, Web of Science and Embase. The following keyword combinations were used: "flavonoidal" OR "flavonoid" OR "flavonoidic" OR "flavonoids" AND "wound healing" as well as MeSH terms, Emtree terms and free-text words. RESULTS: Fifty-five (55) articles met the established inclusion and exclusion criteria. Flavonoids presented effects in respect of the inflammatory process, angiogenesis, re-epithelialization and oxidative stress. They were shown to be able to act on macrophages, fibroblasts and endothelial cells by mediating the release and expression of TGF-ß1, VEGF, Ang, Tie, Smad 2 and 3, and IL-10. Moreover, they were able to reduce the release of inflammatory cytokines, NFκB, ROS and the M1 phenotype. Flavonoids acted by positively regulating MMPs 2, 8, 9 and 13, and the Ras/Raf/MEK/ERK, PI3K/Akt and NO pathways. CONCLUSION: Flavonoids are useful tools in the development of therapies to treat skin lesions, and our review provides a scientific basis for future basic and translational research.

Anticancer activity of limonene: A systematic review of target signaling pathways.

Limonene (LIM) is a monoterpene, which is abundant in essential oils of Citrus fruits peels (Rutaceae). More recently, LIM, as a potential natural anticancer compound, has attracted major attention and exerted a chemopreventive activity, stimulating the detoxification of carcinogenic compounds and limiting tumor growth and angiogenesis in various cancer models. Twenty-six (26) articles were selected based on previously established criteria. Anticancer activity of LIM was related to the inhibition of tumor initiation, growth, and angiogenesis and the induction of cancer cells apoptosis. LIM was able to increase Bax expression, release cytochrome c, and activate the caspase pathway. In addition, LIM increased the expression of p53 and decreased the activity of Ras/Raf/MEK/ERK and PI3K/Akt pathways. LIM also decreased the expression of VEGF and increased the activities of the Man-6-P / IGF2R and TGF-ßIIR receptors. These results highlight LIM as an abundant natural molecule with low toxicity and pleiotropic pharmacological activity in cancer cells, targeting various cell-signaling pathways critically involved in the initiation, growth, and chemoresistance of cancer cells.

Role of peripheral and central sensitization in the anti-hyperalgesic effect of hecogenin acetate, an acetylated sapogenin, complexed with ß-cyclodextrin: Involvement of NFκB and p38 MAPK pathways.

Neuropathic pain develops due to injury to the somatosensory system, affecting the patient's quality of life. In view of the ineffectiveness of the current pharmacotherapy, substances obtained from natural products (NPs) are a promising alternative. One NP that has been discussed in the literature is hecogenin acetate (HA), a steroidal sapogenin with anti-inflammatory and antinociceptive activity. However, HA has low water solubility, which affects its bioavailability. Thus, the objective of this study was to evaluate the anti-hyperalgesic activity of pure and complexed hecogenin acetate (HA/ßCD) in an animal model of chronic neuropathic and inflammatory pain. The inclusion complex was prepared at a molar ratio of 1:2 (HA:ßCD) by the lyophilization method. For the induction of chronic inflammatory pain, the mice received an intraplantar injection of CFA (complete Freund's adjuvant), and were evaluated for mechanical hyperalgesia and for the levels of myeloperoxidase (MPO) in the skin of the paw after eight days of treatment. HA and HA/ßCD reduced mechanical hyperalgesia in relation to the vehicle group until the fourth and fifth hours, respectively, in the acute evaluation, with a superior effect of the complexed form over the pure form in the second and third hour after treatment (p < 0.001). In the chronic evaluation, HA and HA/ßCD reduced hyperalgesia in relation to the vehicle in the eight days of treatment (p < 0.001). Both pure (p < 0.01) and complexed (p < 0.001) forms reduced myeloperoxidase activity in the skin of the animals' paw. Groups of animals subjected to the same pharmacological protocol were submitted to the partial sciatic nerve ligation (PSNL) model and evaluated for mechanical and thermal hyperalgesia, and cold allodynia. HA and HA/ßCD reduced mechanical hyperalgesia until the fourth and sixth hours, respectively, and both reduced hyperalgesia in relation to the vehicle in the chronic evaluation (p < 0.001). HA and HA/ßCD also reduced thermal hyperalgesia and cold allodynia (p < 0.05 and p < 0.001, respectively). The analysis of the spinal cord of these animals showed a decrease in the levels of the pro-inflammatory cytokines TNF-α, IL-1ß and IL-6 and a reduction in the phosphorylation of NFκB and p38MAPK, as well as a decrease in microglioses compared to the vehicle group. In addition, HA/ßCD reduced the nociception induced by intraplantar injection of agonist TRPA1 (p < 0.01) and TRPM8 (p < 0.05). Treatment for eight days with HA and HA/ßCD showed no signs of gastric or liver damage. HA and HA/ßCD were, therefore, shown to have antinociceptive effects in chronic pain models. Based on our exploration of the mechanisms of the action of HA, these effects are likely to be related to inhibited leukocyte migration, interaction with the TRPA1 and TRPM8 receptors, reduced pro-inflammatory cytokines levels, microglial expression and suppression of NF-κB p65 and p38 MAPK pathway signaling. Therefore, HA/ßCD has great potential for use in the treatment of chronic pain.

HPLC-DAD-UV analysis, anti-inflammatory and anti-neuropathic effects of methanolic extract of Sideritis bilgeriana (lamiaceae) by NF-κB, TNF-α, IL-1ß and IL-6 involvement.

Medicinal plants remain an invaluable source for therapeutics of diseases that affect humanity. Sideritis bilgeriana (Lamiaceae) is medicinal plant used in Turkey folk medicine to reduce inflammation and pain, but few studies scientific corroborates its medicinal use so creating a gap between popular use and scientific evidence. Thus, we aimed to evaluate the pharmacological effects of the methanolic extract of S. bilgeriana (MESB) in rodents nociception models and also performed its phytochemical analysis. Firstly, a screening was carried out that enabled the identification of the presence of phenolic compounds and flavonoids. In view of this, a chromatographic method by HPLC-DAD-UV was developed that made it possible to identify chlorogenic acid and its quantification in MESB. MESB-treated mice (MESB 50, 100 and 200 mg/kg, p.o.) reduced mechanical hyperalgesia and myeloperoxidase activity (p < 0.01), and also showed a reduced pain behavior in capsaicin test. In the carrageenan-induced pleurisy test, MESB (100 mg/kg p.o.) significantly reduced the leukocyte (polymorphonuclear) count in the pleural cavity and equally decreased the TNF-α and IL-1ß levels (p < 0.001). In the PSNL model, mechanical hyperalgesia was reduced on the first evaluation day and during the 7 days of evaluation compared to the vehicle group (p < 0.001). Thermal hyperalgesia was also reduced 1 h after treatment compared to the vehicle group (p < 0.001) and reversed the loss of force initially displayed by the animals, thus inferring an analgesic effect in the muscle strength test. Analysis of the marrow of these animals showed a decrease in the level of pro-inflammatory cytokine IL-6 (p < 0.001) and factor NF-κB, in relation to the control group (p < 0.05). Moreover, the MESB treatment produced no noticeable side effects, no disturb in motor performance and no signs of gastric or hepatic injury. Together, the results suggests that MESB could be useful to management of inflammation and neuropathic pain mainly by the management of pro-inflammatory mediators (NF-κB, TNF-α, IL-1ß and IL-6), so reinforcing its use in popular medicine and corroborating the need for further chemical and pharmacological studies for the species.

Resistance training prevents the reduction of insulin-mediated vasodilation in the mesenteric artery of dexamethasone-treated rats.

This study evaluated whether resistance training (RT) could prevent glucocorticoid-induced vascular changes. Wistar rats were divided into groups: control (CO), dexamethasone (DEX), and Dexamethasone+RT (DEX+RT). On the eighth week, dexamethasone was administered in the DEX and DEX+RT groups. Thereafter, the animals were sacrificed and blood samples were used to assess the lipid profile, glucose and insulin. Vascular reactivity to insulin and phenylephrine (Phe) were evaluated. The DEX+RT group presented an improvement in the lipid profile, fasting glucose, and insulin levels compared to the DEX group. In addition, vasodilation was reduced in the DEX group compared to the CO group, and was increased in the DEX+RT group. After inhibition of phosphatidylinositol 3-kinase, DEX group showed contraction, in which it was in the DEX + RT group. When nitric oxide synthase (NOS) participation was evaluated, the DEX group presented a contraction compared to the CO group, with no contractile effect in the DEX+RT group. Moreover, vasoconstriction caused by NOS inhibition was abolished by BQ123 (endothelin receptor antagonist). In respect Phe response, there was an increase in tension in the DEX group compared to the CO group, being reduced in the DEX+RT group. The results suggest that RT prevented damage to vascular reactivity.

Limonene, a food additive, and its active metabolite perillyl alcohol improve regeneration and attenuate neuropathic pain after peripheral nerve injury: Evidence for IL-1ß, TNF-α, GAP, NGF and ERK involvement.

BACKGROUND: Limonene (LIM) and its main metabolite perillyl alcohol (POH) are ingredients found in food with promising chemical entities due to their pharmacological profile. In this study, we hypothesized that LIM and POH are two molecules capable of accelerating the regenerative process and alleviating neuropathic pain. METHODS: Animals were treated daily (LIM, POH and saline) for 28 days and during this period evaluated for mechanical hyperalgesia, astrocyte participation by immunofluorescence for GFAP, and ELISA was used to quantify IL-1ß and TNF-α in the spinal cord. Western blot analysis of the following proteins was also performed: GFAP, GAP-43, NGF and ERK. For motor deficit analysis, tests were performed to assess hind paw muscle strength and footprints through gait (SFI). RESULTS: Both POH and LIM accelerated the regenerative process and improved motor deficits comparing to positive control; however, POH was more effective, particularly between the 2nd and 3rd week after the nerve injury, increasing GAP-43, NGF and the phosphorylated ERK immunocontent. Moreover, POH and LIM were able to reduce hyperalgesia and astrocytosis. CONCLUSIONS: Both substances, LIM and POH, improved the regeneration process and sensory and motor function recovery in the PNI model in mice by mitigating the inflammatory reactions and up-regulating the neurotrophic process.

Evidence for the involvement of IL-1ß and TNF-α in anti-inflammatory effect and antioxidative stress profile of the standardized dried extract from Miconia albicans Sw. (Triana) Leaves (Melastomataceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Miconia albicans (Melastomataceae), commonly known in Brazil as "canela-de-velho", is used in folk medicine for treating rheumatoid arthritis and reducing pain and inflammation. THE AIM OF THE CURRENT WORK WAS: to provide data on physicochemical characterization of the drug plant and dried extract from M. albicans leaves, as well as investigate the anti-inflammatory effect and antioxidant stress profile from the standardized dried extract of this species employing different model systems. MATERIALS AND METHODS: plant material (dried crushed leaves) was extracted by turboextraction using 50% ethanol (v/v). Different pharmacological techniques were performed to establish quality control parameters of the plant drug, and dried extract of M. albicans (DEMA) was chemically characterized by HPLC-PDA to selection of the chemical marker. Total phenolic and flavonoid contents were determined by the Folin-Ciocalteu and AlCl3 colorimetric methods, respectively. Antioxidant potential of the DEMA was investigated by employing different in vitro antioxidant assays, including DPPH and ABTS radical scavenging assays, ferric reducing antioxidant assay, NO scavenging assay, metal ion (Fe2+) chelating activity and antioxidant capacity by inhibition of lipid peroxidation (TBARS). Finally, anti-inflammatory activity of the DEMA was evaluated using two models of acute inflammation: carrageenan induced inflammation and mechanical hyperalgesia. RESULTS AND DISCUSSION: M. albicans leaves, after drying in forced air circulation chamber at ±40 °C for 48 h and crushing in knife mill, presented a moisture content below the maximum allowed for plant drugs (6.4%). The powder of M. albicans was classified as moderately coarse and total ash content was found to be 6.27%. Preliminary phytochemical screening of DEMA revealed the presence of flavonoids, tannins, saponins, leucoanthocyanins and steroids. DEMA had significant higher total phenolic (551.3 mg gallic acid equivalent/g of dried extract) and flavonoid contents (367.19 mg catechin equivalent/g of dried extract). Two major compounds (λ = 340 nm) were identified in DEMA by HPLC-PDA: the flavonoids rutin and quercetin. Rutin content, selected as chemical marker, was determined and found to be 1.16 mg/g dried extract (r = 0.9941). Regarding to antioxidant activity, our results revealed the DEMA exhibited good antioxidant activity on different models. M. albicans treatment also reduced the levels of TNF-α e IL-1ß and consequently inflammatory nociception and edema caused by carrageenan injection. Based on previous studies and our results, is possible to suggest a positive correlation between the flavonoids rutin and quercetin and the antioxidant and anti-inflammatory capacities. CONCLUSION: Together, these data suggest that M. albicans has the possibility of use in conditions such as arthritis or other joint pain, even needing other work to better consolidate this profile.

Dereplication and quantification of the ethanol extract of Miconia albicans (Melastomaceae) by HPLC-DAD-ESI-/MS/MS, and assessment of its anti-hyperalgesic and anti-inflammatory profiles in a mice arthritis-like model: Evidence for involvement of TNF-α, IL-1ß and IL-6.

ETHNOPHARMACOLOGICAL RELEVANCE: Miconia albicans (Sw) Triana (Melastomataceae), a medicinal plant widely used by practitioners of folk medicine in the northeast of Brazil, has been used to treat chronic inflammatory disorders, such as rheumatoid arthritis (RA) and other joint conditions. Oddly, there is little research on the species. AIM OF THE STUDY: We aimed to evaluate the anti-arthritic and anti-inflammatory profile of the ethanolic leaf extract of M. albicans (EEMA), as well as to perform dereplication and quantification by HPLC-DAD-ESI-/MS/MS. MATERIALS AND METHODS: The compounds present in the extracts were identified by HPLC-DAD-ESI-MS/MS. The possible anti-inflammatory effect of EEMA (50 and 100 mg/kg, p.o) was evaluated using the pleurisy model induced by carrageenan and its action on IL-1ß and TNF-α levels was also evaluated. The RA model was induced through the intra-articular injection of complete Freund's adjuvant (CFA). RESULTS: HPLC-DAD-ESI-MS/MS analysis identified 23 compounds, with glycoside flavonoids mainly derived from quercetin, and rutin being the main compounds. EEMA significantly reduced (p < 0.001) leukocyte migration in the pleurisy model and reduced TNF-α and IL-1ß levels in pleural lavage (p < 0.001). In the CFA animal model, EEMA significantly reduced the nociceptive and hyperalgesic behaviors demonstrated by the rearing test (p < 0.01 or p < 0.05) and decreased mechanical hyperalgesia (p < 0.001). EEMA produced a significant improvement in mobility in the open-field test (only at the higher dose, p < 0.05). EEMA significantly (p < 0.01) increased hindpaw grip strength. The diameter of CFA-induced ipsilateral knee edema was significantly reduced (p < 0.001) by EEMA, which was related to reduced levels of IL-6 and TNF-α in the joint knee (p < 0.01). No indication of hepatic injury after chronic treatment was found. CONCLUSION: Taken together, these results contribute to the chemical and pharmacological knowledge of M. albicans and demonstrated that this medicinal plant appears to be able to mitigate deleterious symptoms of RA, which supports its use in folk medicine.

Phytol, a Chlorophyll Component, Produces Antihyperalgesic, Anti-inflammatory, and Antiarthritic Effects: Possible NFκB Pathway Involvement and Reduced Levels of the Proinflammatory Cytokines TNF-α and IL-6.

Phytol is a diterpene constituent of chlorophyll and has been shown to have several pharmacological properties, particularly in relation to the management of painful inflammatory diseases. Arthritis is one of the most common of these inflammatory diseases, mainly affecting the synovial membrane, cartilage, and bone in joints. Proinflammatory cytokines, such as TNF-α and IL-6, and the NFκB signaling pathway play a pivotal role in arthritis. However, as the mechanisms of action of phytol and its ability to reduce the levels of these cytokines are poorly understood, we decided to investigate its pharmacological effects using a mouse model of complete Freund's adjuvant (CFA)-induced arthritis. Our results showed that phytol was able to inhibit joint swelling and hyperalgesia throughout the whole treatment period. Moreover, phytol reduced myeloperoxidase (MPO) activity and proinflammatory cytokine release in synovial fluid and decreased IL-6 production as well as the COX-2 immunocontent in the spinal cord. It also downregulated the p38MAPK and NFκB signaling pathways. Therefore, our findings demonstrated that phytol can be an innovative antiarthritic agent due to its capacity to attenuate inflammatory reactions in joints and the spinal cord, mainly through the modulation of mediators that are key to the establishment of arthritic pain.

Naringenin complexed with hydroxypropyl-ß-cyclodextrin improves the sciatic nerve regeneration through inhibition of p75NTR and JNK pathway.

Peripheral nerve injuries are common conditions that often lead to dysfunctions. Although much knowledge exists on the several factors that mediate the complex biological process involved in peripheral nerve regeneration, there is a lack of effective treatments that ensure full functional recovery. Naringenin (NA) is the most abundant flavanone found in citrus fruits and it has promising neuroprotective, anti-inflammatory and antioxidant effects. This study aimed to enhance peripheral nerve regeneration using an inclusion complex containing NA and hydroxypropyl-ß-cyclodextrin (HPßCD), named NA/HPßCD. A mouse sciatic nerve crush model was used to evaluate the effects of NA/HPßCD on nerve regeneration. Sensory and motor parameters, hyperalgesic behavior and the sciatic functional index (SFI), respectively, improved with NA treatment. Western blot analysis revealed that the levels of p75NTR ICD and p75NTR full length as well phospho-JNK/total JNK ratios were preserved by NA treatment. In addition, NA treatment was able to decrease levels of caspase 3. The concentrations of TNF-α and IL-1ß were decreased in the lumbar spine, on the other hand there was an increase in IL-10. NA/HPßCD presented a better overall morphological profile but it was not able to increase the number of myelinated fibers. Thus, NA was able to enhance nerve regeneration, and NA/HPßCD decreased effective drug doses while maintaining the effect of the pure drug, demonstrating the advantage of using the complex over the pure compound.

[Association between peripheral perfusion, microcirculation and mortality in sepsis: a systematic review]. / Associação entre perfusão periférica, microcirculação e mortalidade em sepse: uma revisão sistemática.

Although increasing evidence supports the monitoring of peripheral perfusion in septic patients, no systematic review has been undertaken to explore the strength of association between poor perfusion assessed in microcirculation of peripheral tissues and mortality. A search of the most important databases was carried out to find articles published until February 2018 that met the criteria of this study using different keywords: sepsis, mortality, prognosis, microcirculation and peripheral perfusion. The inclusion criteria were studies that assessed association between peripheral perfusion/microcirculation and mortality in sepsis. The exclusion criteria adopted were: review articles, animal/pre-clinical studies, meta-analyzes, abstracts, annals of congress, editorials, letters, case-reports, duplicate and articles that did not present abstracts and/or had no text. In the 26 articles were chosen in which 2465 patients with sepsis were evaluated using at least one recognized method for monitoring peripheral perfusion. The review demonstrated a heterogeneous critically ill group with a mortality-rate between 3% and 71% (median=37% [28%-43%]). The most commonly used methods for measurement were Near-Infrared Spectroscopy (NIRS) (7 articles) and Sidestream Dark-Field (SDF) imaging (5 articles). The vascular bed most studied was the sublingual/buccal microcirculation (8 articles), followed by fingertip (4 articles). The majority of the studies (23 articles) demonstrated a clear relationship between poor peripheral perfusion and mortality. In conclusion, the diagnosis of hypoperfusion/microcirculatory abnormalities in peripheral non-vital organs was associated with increased mortality. However, additional studies must be undertaken to verify if this association can be considered a marker of the gravity or a trigger factor for organ failure in sepsis.

Association between peripheral perfusion, microcirculation and mortality in sepsis: a systematic review / Associação entre perfusão periférica, microcirculação e mortalidade em sepse: uma revisão sistemática

Abstract Although increasing evidence supports the monitoring of peripheral perfusion in septic patients, no systematic review has been undertaken to explore the strength of association between poor perfusion assessed in microcirculation of peripheral tissues and mortality. A search of the most important databases was carried out to find articles published until February 2018 that met the criteria of this study using different keywords: sepsis, mortality, prognosis, microcirculation and peripheral perfusion. The inclusion criteria were studies that assessed association between peripheral perfusion/microcirculation and mortality in sepsis. The exclusion criteria adopted were: review articles, animal/pre-clinical studies, meta-analyzes, abstracts, annals of congress, editorials, letters, case-reports, duplicate and articles that did not present abstracts and/or had no text. In the 26 articles were chosen in which 2465 patients with sepsis were evaluated using at least one recognized method for monitoring peripheral perfusion. The review demonstrated a heterogeneous critically ill group with a mortality-rate between 3% and 71% (median = 37% [28%-43%]). The most commonly used methods for measurement were Near-Infrared Spectroscopy (NIRS) (7 articles) and Sidestream Dark-Field (SDF) imaging (5 articles). The vascular bed most studied was the sublingual/buccal microcirculation (8 articles), followed by fingertip (4 articles). The majority of the studies (23 articles) demonstrated a clear relationship between poor peripheral perfusion and mortality. In conclusion, the diagnosis of hypoperfusion/microcirculatory abnormalities in peripheral non-vital organs was associated with increased mortality. However, additional studies must be undertaken to verify if this association can be considered a marker of the gravity or a trigger factor for organ failure in sepsis.

Resumo Embora evidências crescentes apoiem a monitoração da perfusão periférica em pacientes sépticos, nenhuma revisão sistemática foi feita para explorar a força da associação entre a má perfusão avaliada na microcirculação dos tecidos periféricos e a mortalidade. Uma busca nas bases de dados mais importantes foi feita para encontrar artigos publicados até fevereiro de 2018 que correspondessem aos critérios deste estudo, com diferentes palavras-chave: sepse, mortalidade, prognóstico, microcirculação e perfusão periférica. Os critérios de inclusão foram estudos que avaliaram a associação entre perfusão/microcirculação periférica e mortalidade em sepse. Os critérios de exclusão adotados foram os seguintes: artigos de revisão, estudos com animais/pré-clínicos, metanálises, resumos, anais de congressos, editoriais, cartas, relatos de casos, artigos duplicados e artigos que não continham resumos e/ou texto. Foram selecionados 26 artigos nos quais 2465 pacientes com sepse foram avaliados com pelo menos um método reconhecido para monitorar a perfusão periférica. A revisão demonstrou um grupo heterogêneo de pacientes gravemente enfermos com uma taxa de mortalidade entre 3% e 71% (mediana = 37% [28%-43%]). Os métodos de avaliação mais comumente usados foram a espectroscopia na região do infravermelho próximo (Near-Infrared Spectroscopy - NIRS) (7 artigos) e a análise de imagens em campo escuro (Sidestream Dark-Field - SDF) (5 artigos). O leito vascular mais avaliado foi a microcirculação sublingual/bucal (8 artigos), seguida pela ponta do dedo (4 artigos). A maioria dos estudos (23 artigos) demonstrou uma clara relação entre má perfusão periférica e mortalidade. Em conclusão, o diagnóstico de hipoperfusão/anormalidades microcirculatórias em órgãos não vitais periféricos foi associado ao aumento da mortalidade. No entanto, estudos adicionais devem ser feitos para verificar se essa associação pode ser considerada um marcador da gravidade ou um fator desencadeante da falência de órgãos na sepse.

Involvement of the PKA pathway and inhibition of voltage gated Ca2+ channels in antihyperalgesic activity of Lippia grata/ß-cyclodextrin.

Neuropathic pain (NP) is a difficult condition to treat because of the modest efficacy of available drugs. New treatments are required. In the study we aimed to investigate the effects of the essential oil from Lippia grata alone or complexed in ß-cyclodextrin (LG or LG-ßCD) on persistent inflammatory and neuropathic pain in a mouse model. We also investigated Ca2+ currents in rat dorsal root ganglion (DRG) neurons. Male Swiss mice were treated with LG or LG/ß-CD (24 mg/kg, i.g.) and their effect was evaluated using an acute inflammatory pleurisy model and nociception triggered by intraplantar injection of an agonist of the TRPs channels. We also tested their effect in chronic pain models: injection of Freund's Complete Adjuvant and partial sciatic nerve ligation (PSNL). In the pleurisy model, LG reduced the number of leukocytes and the levels of TNF-α and IL-1ß. It also inhibited cinnamaldehyde and menthol-induced nociceptive behavior. The pain threshold in mechanical and thermal hyperalgesia was increased and paw edema was decreased in models of inflammatory and neuropathic pain. PSNL increased inflammatory protein contents and LG and LG-ßCD restored the protein contents of TNF-α, NF-κB, and PKA, but not IL-1ß and IL-10. LG inhibited voltage gated Ca2+ channels from DRG neurons. Our results suggested that LG or LG-ßCD produce anti-hyperalgesic effect in chronic pain models through reductions in TNF-α levels and PKA, and inhibited voltage-gated calcium channels and may be innovative therapeutic agents for the management of NP.

Anti-hyperalgesic and anti-inflammatory effects of citral with ß-cyclodextrin and hydroxypropyl-ß-cyclodextrin inclusion complexes in animal models.

Citral (CIT) is a monoterpene formed by the geranial and neral stereoisomers. CIT is the major compound of Cymbopogon citratus essential oil, commonly known as "lemongrass", and has demonstrated potential antihyperalgesic, anti-nociceptive and anti-inflammatory effects. However, CIT shows high volatility, low solubility in water and consequent low bioavailability, which limits its use. Therefore, the aim of this study was to evaluate cell viability, anti-hyperalgesic and anti-inflammatory effects of inclusion complexes of CIT on ß-cyclodextrin (ß-CD) and hydroxypropyl-ß-cyclodextrin (HP-ß-CD). Initially, physical mixture (PM) and freeze-dried inclusion (FD) complexes of CIT/ß-CD and CIT/HP-ß-CD were obtained in the molar ratio (1:1). The samples were characterized by DSC, TG/DTG, FT-IR, XRD, SEM and the complexation efficiency were performed by HPLC. Cell viability assay was performed by rezasurin reduction technique in J774 macrophages cell line. The motor activity through rota rod apparatus, mechanical hyperalgesia and pleurisy induced by carrageenan were evaluated in mice. The complexation of CIT was evidenced with ß-CD and HP-ß-CD by the characterization techniques analyzed. The complexation efficiency of CIT/ß-CD and CIT/HP-ß-CD were 78.6% and 71.7%, respectively. The CIT, CIT/ß-CD and CIT/HP-ß-CD showed cell viability in macrophages and did not interfere in the motor activity of mice. Besides that, the samples demonstrated antihyperalgesic and anti-inflammatory activity due to the reduction in total leukocytes and TNF-α levels. However, CIT/ß-CD has better pharmacological effects among the three samples evaluated. Therefore, CIT/ß-CD has potential for the development of products to treat inflammatory and pain reactions.

Central nervous system and analgesic profiles of Lippia genus

Abstract Many people use medicinal plants to relieve disorders related to the central nervous system, such as depression, epilepsy, anxiety and pain, even though the effectiveness of most of them has not yet been proven through scientific studies. Plants of the Lippia genus, Verbenaceae, are widely used in ethnobotany as a food, for seasoning and in antiseptic remedies. They are also marketed and used for the treatment of different types of pain, including stomach ache, abdominal pain and headache, as well as being used as sedatives, anxiolytics and anticonvulsants. Despite their widespread use, there are no reviews on the central nervous system profile of plants of this genus. Therefore, the databases Medline-PubMed, Embase, Scopus and Web of Science were searched using the terms Lippia and biologic activity. Thirty-five papers were found. Eleven species of Lippia showed central nervous system activity, with leaves and the aerial parts of plants being the most commonly used, especially in aqueous and ethanol extracts or volatile oil. The species are composed mainly of terpenoids and phenylpropanoids, including polyketides, flavonoids and in less quantity some alkaloids. Although several species of Lippia present analgesic activity, most studies have not explored the mechanisms responsible for this effect, however, there is some evidence that volatile oils and constituents of the extracts may be responsible for the relief of some CNS disorders, but the effects on pain modulation seem to be the most exploited so far.