Pomegranate extract in polyphosphate-fluoride mouthwash reduces enamel demineralization.

OBJECTIVES: To evaluate the anti-demineralizing effect of a mouthwash comprising pomegranate peel extract (PPE 3%), sodium trimetaphosphate (TMP 0.3%), and fluoride (F 225 ppm) in an in situ study, and to assess its irritation potential in an ex vivo study. METHODS: This double-blind crossover study was conducted in four phases with 7 days each. Twelve volunteers used palatal appliances containing enamel blocks, which were subjected to cariogenic challenges. The ETF formulation (PPE + TMP + F, pH 7.0), TF formulation (TMP + F, pH 7.0), deionized water (W, pH 7.0), and essential oil commercial mouthwash (CM, 220 ppm F, pH 4.3) were dropped onto the enamel twice daily. The percentage of surface hardness loss, integrated loss of subsurface hardness, calcium, phosphorus, and fluoride in enamel and biofilms were determined. In addition, alkali-soluble extracellular polysaccharide concentrations were analyzed in the biofilms. The irritation potential was evaluated using the hen's egg chorioallantoic membrane test through the vascular effect produced during 300-s of exposure. RESULTS: ETF was the most efficacious in preventing demineralization. It also showed the highest concentrations of calcium and phosphorus in the enamel and in the biofilm, as well as the lowest amount of extracellular polysaccharides in the biofilm. In the eggs, ETF produced light reddening, whereas CM led to hyperemia and hemorrhage. CONCLUSIONS: The addition of PPE to formulations containing TMP and F increased its anti-demineralizing property, and this formulation presented a lower irritation potential than the CM. CLINICAL RELEVANCE: ETF can be a promising alternative alcohol-free mouthwash in patients at high risk of caries.

Toxicological Profile and Anti-Inflammatory Effect of Mucoadhesive Gel from Residues of Agave sisalana and Punica granatum.

Inflammation is a natural protective reaction of the body against endogenous and exogenous damage, such as tissue injuries, trauma, and infections. Thus, when the response is adequate, inflammation becomes a defense mechanism to repair damaged tissue, whereas when the response is inadequate and persistent, the increase in inflammatory cells, cytosines, and chymosins impair tissue regeneration and promote a response harmful to the organism. One example is chronic tissue inflammation, in which a simple lesion can progress to ulcers and even necrosis. In this situation, the anti-inflammatory medications available in therapy are not always effective. For this reason, the search for new treatments, developed from medicinal plants, has increased. In this direction, the plants Agave sisalana (sisal) and Punica granatum (pomegranate) are rich in saponins, which are secondary metabolites known for their therapeutic properties, including anti-inflammatory effects. Although Brazil is the world's leading sisal producer, approximately 95% of the leaves are discarded after fiber extraction. Similarly, pomegranate peel waste is abundant in Brazil. To address the need for safe and effective anti-inflammatory treatments, this study aimed to create a topical mucoadhesive gel containing a combination of sisal (RS) and pomegranate residue (PR) extracts. In vitro experiments examined isolated and combined extracts, as well as the resulting formulation, focusing on (1) a phytochemical analysis (total saponin content); (2) cytotoxicity (MTT assay); and (3) a pharmacological assessment of anti-inflammatory activity (phagocytosis, macrophage spreading, and membrane stability). The results revealed saponin concentrations in grams per 100 g of dry extract as follows: SR-29.91 ± 0.33, PR-15.83 ± 0.93, association (A)-22.99 ± 0.01, base gel (G1)-0.00 ± 0.00, and association gel (G2)-0.52 ± 0.05. In MTT tests for isolated extracts, cytotoxicity values (µg/mL) were 3757.00 for SR and 2064.91 for PR. Conversely, A and G2 exhibited no cytotoxicity, with increased cell viability over time. All three anti-inflammatory tests confirmed the presence of this activity in SR, PR, and A. Notably, G2 demonstrated an anti-inflammatory effect comparable to dexamethasone. In conclusion, the gel containing SR and PR (i.e., A) holds promise as a novel herbal anti-inflammatory treatment. Its development could yield economic, social, and environmental benefits by utilizing discarded materials in Brazil.

Analysis of antioxidant, cytotoxic and mutagenic potential of Agave sisalana Perrine extracts using Vero cells, human lymphocytes and mice polychromatic erythrocytes.

Brazilian Northeast is the world's largest producer of Agave sisalana Perrine for the supply of the sisal fiber. About 95% of plant biomass, which comprise the mucilage and sisal juice, is considered a waste residual is discarded in the soil. However, the sisal juice is rich in steroidal saponins, which exhibits different pharmacological properties. Despite this, natural products are not necessarily safe. Based on this, this study analyzed the antioxidant, cytotoxic and mutagenic potential of three extracts derived from acid hydrolysis (AHAS), dried precipitate (DPAS) and hexanic of A. sisalana (HAS). These analyses were performed by in vitro and in vivo methods, using Vero cells, human lymphocytes and mice. Results showed that AHAS 50 and 100 can be considered a useful antineoplastic candidate due to their antioxidant and cytotoxic activity, with no genotoxic/clastogenic potential in Vero cells and mice. Although the comet assay in human lymphocytes has showed that the AHAS 25, AHAS 50 and AHAS 100 can lead to DNA breaks, these extracts did not promote DNA damages in mice bone marrow. Considering the different mutagenic responses obtained with the different methods employed, this study suggest that the metabolizing pathways can produce by-products harmful to health. For this reason, it is mandatory to analyze the mutagenic potential by both in vitro and in vivo techniques, using cells derived from different species and origins.

Platelet-rich plasma (PRP): methodological aspects and clinical applications.

The clinical use of platelet-rich plasma (PRP) is based on the increase in the concentration of growth factors and in the secretion of proteins which are able to maximize the healing process at the cellular level. Since PRP is an autologous biologic material, it involves a minimum risk of immune reactions and transmission of infectious and contagious diseases, and it has been widely used for the recovery of musculoskeletal lesions. Despite the great potential for applicability, the implementation of the therapeutic employment of PRP as a clinical alternative has become difficult, due to the lack of studies related to the standardization of the techniques and/or insufficient description of the adopted procedures. Therefore, it is required establish standard criteria to be followed for obtaining a PRP of high quality, as well as a larger number of studies which should establish the proper concentration of platelets for the different clinical conditions. In this context, the purpose of this review is to discuss some methodological aspects used for achieving the PRP, as well as to discuss the bioactive properties of PRP, and to point out its therapeutic use in different fields of regenerative medicine.

Social separation and diazepam withdrawal increase anxiety in the elevated plus-maze and serotonin turnover in the median raphe and hippocampus.

The present work aimed to evaluate the effects of social separation for 14 days (chronic stress) and of withdrawal from a 14-day treatment with diazepam (acute stress) on the exploratory behaviour of male rats in the elevated plus-maze and on serotonin (5-hydroxytryptamine) turnover in different brain structures. Social separation had an anxiogenic effect, evidenced by fewer entries into, and less time spent on the open arms of the elevated plus-maze. Separation also selectively increased 5-hydroxytryptamine turnover in the hippocampus and median raphe nucleus. Diazepam withdrawal had a similar anxiogenic effect in grouped animals and increased 5-hydroxytryptamine turnover in the same brain structures. Chronic treatment with imipramine during the 14 days of separation prevented the behavioural and neurochemical changes caused by social separation. It is suggested that the increase in anxiety determined by both acute and chronic stress is mediated by the activation of the median raphe nucleus-hippocampal 5-hydroxytryptamine pathway.

Involvement of median raphe nucleus 5-HT1A receptors in the regulation of generalized anxiety-related defensive behaviours in rats.

Changes in 5-HT1A receptor-mediated neurotransmission at the level of the median raphe nucleus (MRN) are reported to affect the expression of defensive responses that are associated with generalized anxiety disorder (e.g. inhibitory avoidance) but not with panic (e.g. escape). The objective of this study was to further explore the involvement of MRN 5-HT1A receptors in the regulation of generalized anxiety-related behaviours. Results of experiment 1 showed that intra-MRN injection of the 5-HT1A/7 receptor agonist 8-OH-DPAT (0.6 nmol) in male Wistar rats impaired the acquisition of inhibitory avoidance, without interfering with the performance of escape in the elevated T-maze test of anxiety. Pre-treatment with the 5-HT1A receptor antagonist WAY-100635 (0.18 nmol) fully blocked this anxiolytic-like effect. As revealed by experiment 2, intra-MRN injection of 8-OH-DPAT (0.6, 3 or 15 nmol) also caused anxiolytic effect in rats submitted to the light-dark transition test, another animal model that has been associated with generalized anxiety. In the same test, intra-MRN injection of WAY-100635 (0.18, 0.37 or 0.74 nmol) caused the opposite effect. Overall, the current findings support the view that MRN 5-HT neurons, through the regulation of 5-HT1A somatodendritic autoreceptors, are implicated in the regulation of generalized anxiety-associated behaviours.

5-HT1A receptors in the dorsal hippocampus mediate the anxiogenic effect induced by the stimulation of 5-HT neurons in the median raphe nucleus.

We evaluated the involvement of dorsal hippocampus (DH) 5-HT1A receptors in the mediation of the behavioral effects caused by the pharmacological manipulation of 5-HT neurons in the median raphe nucleus (MRN). To this end, we used the rat elevated T-maze test of anxiety. The results showed that intra-DH injection of the 5-HT1A/7 agonist 8-OH-DPAT facilitated inhibitory avoidance, an anxiogenic effect, without affecting escape. Microinjection of the 5-HT1A antagonist WAY-100635 was ineffective. In the elevated T-maze, inhibitory avoidance and escape have been related to generalized anxiety and panic disorders, respectively. Intra-MRN administration of the excitatory amino acid kainic acid, which non-selectively stimulates 5-HT neurons in this brain area facilitated inhibitory avoidance and impaired escape performance, but also affected locomotion. Intra-MRN injection of WAY-100635, which has a disinhibitory effect on the activity of 5-HT neurons in this midbrain area, only facilitated inhibitory avoidance. Pre-administration of WAY-100635 into the DH blocked the behavioral effect of intra-MRN injection of WAY-100635, but not of kainic acid. These results indicate that DH 5-HT1A receptors mediate the anxiogenic effect induced by the selective stimulation of 5-HT neurons in the MRN.

Serotonergic neurons in the median raphe nucleus regulate inhibitory avoidance but not escape behavior in the rat elevated T-maze test of anxiety.

RATIONALE: A wealth of evidence supports the involvement of the serotonergic neurons of the median raphe nucleus (MRN) in anxiety. However, it is presently unclear whether serotonergic pathways arising from this nucleus play distinguishing regulatory roles in defensive behaviors that have been associated with specific subtypes of anxiety disorders. OBJECTIVES: To evaluate the role of the MRN serotonergic neurons in the regulation of two defensive behaviors, inhibitory avoidance and escape, which have been related, respectively, to generalized anxiety and panic disorders. METHODS: Male Wistar rats were submitted to the elevated T-maze test of anxiety after intra-MRN administration of drugs that either non-selectively or selectively change the activity of the serotonergic neurons. RESULTS: Intra-MRN injection of FG 7142 (0.04 and 0.08 nmol) and kainic acid (0.03 and 0.06 nmol), drugs that non-selectively stimulate the MRN serotonergic neurons, facilitated inhibitory avoidance acquisition, but impaired escape performance. Microinjection of muscimol (0.11 and 0.22 nmol), a compound that non-selectively inhibits the activity of the MRN serotonergic neurons, impaired inhibitory avoidance and facilitated escape performance. Both kainic acid and muscimol also changed rat locomotion in the open-field test. Intra-MRN injection of 8-OH-DPAT (0.6-15 nmol) and WAY-100635 (0.18-0.74 nmol), respectively an agonist and an antagonist of somatodendritic 5-HT(1A) receptors located on serotonergic neurons of the MRN, only affected inhibitory avoidance-while the former inhibited the acquisition of this behavior, the latter facilitated it. CONCLUSION: MRN serotonergic neurons seem to be selectively involved in the regulation of inhibitory avoidance in the elevated T-maze. This result supports the proposal that 5-HT pathways departing from this nucleus play an important role in anxiety processing, with implications for pathologies such as generalized anxiety disorder.