Neuropeptídeos na pele

Comparative analysis of two laser wavelengths in the stimulation of acupuncture points for analgesic effects in an animal model

This study compares the effectiveness of two laser wavelengths for stimulating acupoints in an experimental model of acute postoperative pain. Forty-five Wistar rats were randomly assigned to receive treatment on their left hind paw, contralateral to a surgical procedure. Laser treatments were performed with Green Laser-GL (532 nm, 70 mW and 7 J/cm² of energy), Red Laser-RL (660 nm, 100 mW and 7 J/cm² of energy), or with Laser Off-LO. After each application, the animals were evaluated with a Von Frey analgesiometer to check for painful sensitivity on their right (with surgery) and left (without surgery) hind paws. Neuropeptides and cytokine levels in the incision site tissue of the right paw were measured by ELISA after 1, 6 and 24 hours. It was possible to observe that, in this pain model, both lasers promoted analgesia and that the GL altered the levels of TNF-α and IL-1β.

Atopic dermatitis: allergic dermatitis or neuroimmune dermatitis?

Advances in knowledge of neurocellulars relations have provided new directions in the understanding and treatment of numerous conditions, including atopic dermatitis. It is known that emotional, physical, chemical or biological stimuli can generate more accentuated responses in atopic patients than in non-atopic individuals; however, the complex network of control covered by these influences, especially by neuropeptides and neurotrophins, and their genetic relations, still keep secrets to be revealed. Itching and airway hyperresponsiveness, the main aspects of atopy, are associated with disruption of the neurosensory network activity. Increased epidermal innervation and production of neurotrophins, neuropeptides, cytokines and proteases, in addition to their relations with the sensory receptors in an epidermis with poor lipid mantle, are the aspects currently covered for understanding atopic dermatitis.

Reaction time and replenishment time of SP and CGRP after incision in rat skin

Background. The skin neurogenic inflammation is mainly related to Substance P (SP) and Calcitonin Gene-related Peptide (CGRP). There is no data on their availability in the dynamics of skin nerve endings, concerning their release and replenishment after a nociceptive stimulus, so this was investigated. Materials and methods. 25 rats were randomly distributed in 5 groups. The animals of the control group (CG) determined the baseline levels of neuropeptides in the skin. The groups S0 and S30 did not receive any cutaneous stimulus at 30 and 60 minutes, respectively. In the group S1, an “incision stimulus” was made at 30 minutes. In the group S31, a nociceptive stimulus was performed by subdermal scratching at 30 minutes and, at 60 minutes, the “incision stimulus” was carried out in the same location (“nociceptive hyperstimulation”). The skin samples of the other animals were harvested from the back 1 minute after their death. SP, pro-CGRP and CGRP were quantified by Western Blotting. Results. The “incision stimulus” released SP, S1 compared to S0 (p <0.05) detected in the first minute, and the replenishment time was more than 30 minutes. Also, it cleaved pro-CGRP, S1 compared to S31 (p <0.05) in the first minute, and its replenishment time less than 30 minutes. Release of CGRP was not detected. Conclusion. The incision released SP already detected in the first minute; its replenishment time is more than 30 minutes. The incision decreased pro-CGRP, also detected in the first minute; and its replenishment time is less than 30 minutes.

From popular use to pharmacological validation: a study of the anti-inflammatory, anti-nociceptive and healing effects of Chenopodium ambrosioides extract

ETHNO-PHARMACOLOGICAL RELEVANCE: Chenopodium ambrosioides (Amarantaceae) is an annual or perennial plant popularly known as 'erva de Santa Maria', 'mastruço' and 'erva-do-formigueiro'. This herb is used in folk medicine in the form of teas, poultices and infusions for inflammatory problems, contusions and lung infections, and as an anthelmintic and anti-fungal.

AIM OF THE STUDY

The aim of the present study was to further the understanding of the anti-nociceptive, anti-inflammatory and wound healing effects of ethanol extract (EE) obtained from the leaves and stems of Chenopodium ambrosioides in animal models of acute pain, inflammation and wound healing, thus supporting its medicinal use for the treatment of pain and inflammatory conditions

MATERIALS AND METHODS

The anti-nociceptive activity of EE (150-500 mg/kg) was evaluated using the nociception induced by formalin (2.5%), prostaglandin-E(2) (PGE2; 3 nmol/paw), capsaicin (CAP, 1.6 μg/paw) and bradykinin (BK, 10 nmol/paw). The anti-inflammatory activity of EE (150-500 mg/kg) was evaluated in carrageenan- (Cg, 300 μg/paw), PGE(2)- (3 nmol/paw), substance P- (SP, 20 nmol/paw) and BK- (3 nmol/paw) induced paw oedema. The topical anti-inflammatory activity of EE (1%, 3% and 5%) was evaluated in arachidonic acid- (AA, 2mg/ear), oil croton- (1 μg/ear) and CAP- (250 μg/ear) induced ear oedema. The effect of this extract in the inhibition of the influx of neutrophil, myeloperoxidase (MPO) and adenosine-deaminase (ADA) activities and nitric oxide (NO) and TNF-á levels was also determined using the mouse of pleurisy induced by Cg. The excision wound model in rats was used to evaluate the wound healing efficacy of EE (1%, 3% and 5%). To exclude the possible non-specific muscle relaxant or sedative effects of EE, mice motor performance was also evaluated with the rota-rod test.

RESULTS

EE (5% per ear) was effective in reducing ear oedema induced by croton oil by 78.09%, CAP by 70.85% and AA by 77.02%. EE (500 mg/kg; p.o.) also significantly inhibited paw oedema induced by Cg by 40%, PGE(2) by 51%, SP by 56% and BK by 57%. EE (500 mg/kg; p.o.) inhibited the cell influx of leucocytes by 78% and neutrophils by 53%, MPO activity by 62.22% and ADA activity by 23.07%, as well as NO by 77.77% and TNF-á levels by 50% in the fluid leakage due to the carrageenan-induced pleurisy. EE also inhibited the formalin-induced nociceptive in both phases of pain (neurogenic and inflammatory) at a dose of 500 mg/kg, resulting in inhibitions of 77.39% and 95.60%, respectively. EE (500 mg/kg; p.o.) was also effective in inhibiting the nociception induced by PGE(2) (68%), CAP (53%) and BK (32%). Topical application of EE (5%) on excision wounds caused a significant reduction in wound area when compared with the untreated controls. Finally, treatment with EE (150-500 mg/kg) did not show any significant alterations in motor performance or body temperature compared with the control group.

CONCLUSIONS

The results, including the inhibition of mediators (BK, NO, SP, PGE(2) and TNF-á) and enzyme (MPO and ADA) activity, validate the use of the plant under study for therapeutic treatment of anti-inflammatory, painful and wound healing processes.

Immune cells recruitment and activation by Tityus serrulatus scorpion venom

Despite several studies showed that the Tityus serrulatus scorpion venom (Tsv) induces an inflammatory response, just a few have investigated the effect of the venom on the immune response. Therefore, the aim of this study was to evaluate alterations of venom application on lymphoid organs and on the recruitment and activation of cells and also on the cytokine production. Swiss male mice (2-3 months, 20-25 g) received a non-lethal dose of crude Tsv (200 μg/kg), diluted in sterile PBS by subcutaneous route. Control animals received only sterile PBS. The animals were sacrificed after 30, 120 and 360 min. The inflammatory parameters studied were skin histology at the site of venom application, leukocyte count, and blood cytokine levels (IL-6, IL-10, and TNF-α). Inguinal lymph node, spleen and bone marrow cellularity was determined for evaluation of the Tsv effect on immune system organs. The results showed that Tsv caused no local inflammation, but it induced an increase of blood neutrophils and serum IL-6, TNF-α and IL-10. After 360 min of envenomation there was a reduction in the cells number from peritoneum and spleen, but there was an increase in the cell number from lymph nodes. In conclusion, the Tsv induces systemic alterations characterized by changes in the cell number in lymphoid organs, increase pro and anti-inflammatory cytokines.

Vasculopatia livedóide: relato de caso com possível evidência de etiopatogenia neurovascular

A etiopatogênese da vasculopatia livedóide ainda hoje permanece indeterminada e, apesar de algumas etiologias aventadas, com freqüência elas não apresentam associação com a vasculopatia em seu curso. Os tratamentos descritos na literatura não apresentam resultados reproduzíveis. Relata-se caso de paciente de 42 anos, com vasculopatia livedóide e boa resposta ao tratamento pioneiro com a carbamazepina. A droga foi instituída diante das discretas evidências de inflamação, da inconstância dos achados relacionados às teorias sugeridas, da forte sintomatologia dolorosa e dos recentes relatos da participação neural na coagulação, que levaram os autores a considerar a possibilidade de associação vasculoneural na patogênese dessa vasculopatia.