Bergenin Reduces Experimental Painful Diabetic Neuropathy by Restoring Redox and Immune Homeostasis in the Nervous System.

Diabetic neuropathy is a frequent complication of diabetes. Symptoms include neuropathic pain and sensory alterations-no effective treatments are currently available. This work characterized the therapeutic effect of bergenin in a mouse (C57/BL6) model of streptozotocin-induced painful diabetic neuropathy. Nociceptive thresholds were assessed by the von Frey test. Cytokines, antioxidant genes, and oxidative stress markers were measured in nervous tissues by ELISA, RT-qPCR, and biochemical analyses. Single (3.125-25 mg/kg) or multiple (25 mg/kg; twice a day for 14 days) treatments with bergenin reduced the behavioral signs of diabetic neuropathy in mice. Bergenin reduced both nitric oxide (NO) production in vitro and malondialdehyde (MDA)/nitrite amounts in vivo. These antioxidant properties can be attributed to the modulation of gene expression by the downregulation of inducible nitric oxide synthase (iNOS) and upregulation of glutathione peroxidase and Nrf2 in the nervous system. Bergenin also modulated the pro- and anti-inflammatory cytokines production in neuropathic mice. The long-lasting antinociceptive effect induced by bergenin in neuropathic mice, was associated with a shift of the cytokine balance toward anti-inflammatory predominance and upregulation of antioxidant pathways, favoring the reestablishment of redox and immune homeostasis in the nervous system. These results point to the therapeutic potential of bergenin in the treatment of painful diabetic neuropathy.

Bone marrow-derived mesenchymal stem/stromal cells reverse the sensorial diabetic neuropathy via modulation of spinal neuroinflammatory cascades.

BACKGROUND: Diabetic neuropathy (DN) is a frequent and debilitating manifestation of diabetes mellitus, to which there are no effective therapeutic approaches. Mesenchymal stem/stromal cells (MSC) have a great potential for the treatment of this syndrome, possibly through regenerative actions on peripheral nerves. Here, we evaluated the therapeutic effects of MSC on spinal neuroinflammation, as well as on ultrastructural aspects of the peripheral nerve in DN-associated sensorial dysfunction. METHODS: C57Bl/6 mice were treated with bone marrow-derived MSC (1 × 106), conditioned medium from MSC cultures (CM-MSC) or vehicle by endovenous route following the onset of streptozotocin (STZ)-induced diabetes. Paw mechanical and thermal nociceptive thresholds were evaluated by using von Frey filaments and Hargreaves test, respectively. Morphological and morphometric analysis of the sciatic nerve was performed by light microscopy and transmission electron microscopy. Mediators and markers of neuroinflammation in the spinal cord were measured by radioimmunoassay, real-time PCR, and immunofluorescence analyses. RESULTS: Diabetic mice presented behavioral signs of sensory neuropathy, mechanical allodynia, and heat hypoalgesia, which were completely reversed by a single administration of MSC or CM-MSC. The ultrastructural analysis of the sciatic nerve showed that diabetic mice exhibited morphological and morphometric alterations, considered hallmarks of DN, such as degenerative changes in axons and myelin sheath, and reduced area and density of unmyelinated fibers. In MSC-treated mice, these structural alterations were markedly less commonly observed and/or less pronounced. Moreover, MSC transplantation inhibited multiple parameters of spinal neuroinflammation found in diabetic mice, causing the reduction of activated astrocytes and microglia, oxidative stress signals, galectin-3, IL-1ß, and TNF-α production. Conversely, MSC increased the levels of anti-inflammatory cytokines, IL-10, and TGF-ß. CONCLUSIONS: The present study described the modulatory effects of MSC on spinal cord neuroinflammation in diabetic mice, suggesting new mechanisms by which MSC can improve DN.

Patent Mining on the Use of Antioxidant Phytochemicals in the Technological Development for the Prevention and Treatment of Periodontitis.

Periodontal disease is an inflammatory condition characterized by an aberrant immune response against a dysbiotic dental biofilm, with oxidative stress performing an essential role in its pathogenesis. This paper presents a patent mining, performed in the Orbit Intelligence patent database, related to antioxidant phytochemicals in the technological developments that are working to prevent and treat periodontal disease. To access the documents, the descriptors "PERIODONTAL" and "ANTIOXIDANT" were typed in the title, abstract, and claim search fields. A total of 322 patents demonstrate the growing interest in researching natural antioxidants for scientific and technological purposes. The top ten countries regarding the number of family patents produced were the United States, the European Office, Japan, South Korea, China, India, Mexico, Denmark, Canada, and Great Britain. The most cited compounds were vitamin C, green tea, quercetin, melatonin, lycopene, resveratrol, and curcumin. These compounds have been used for the technological development of gels, membranes, dentifrices, chewing gum, orally disintegrating film, mouthwash, mouth spray, and mouth massage cream and exhibit the ability to neutralize free radicals and reduce oxidative stress, a critical factor in the development and progression of periodontal diseases. The patent documents have shown that using antioxidant compounds in conjunction with traditional periodontal treatments is a promising area of interest in periodontal therapy.

Technological Trends Involving Probiotics in the Treatment of Diabetic Neuropathy: A Patent Review (2009-2022).

BACKGROUND: Diabetic neuropathy (DN) causes neuropathic pain, and current treatments are unsatisfactory. Recently studies have demonstrated an assertive correlation between gut microbiota and pain modulation. OBJECTIVE: Considering the emerging search for new therapies for the control of DN and the growing commercial interest in the probiotics market, this study aimed to provide patents on the use of probiotics in the control of DN. METHODS: This is a patent prospection performed in the Espacenet Patent database, using the association of keywords and IPC related to probiotics in medical preparations and foods, from 2009 to December 2022. RESULTS: Results have shown that in 2020, there was a boom in patent filing in the area. Asian countries accounted for more than 50% of all 48 inventions (n = 48), with Japan as the only applicant in 2021. Products being developed in recent years point to effects that may represent an advancement in DN treatment, such as reduced concentration of pro-inflammatory mediators, metabolites and neurotransmitters release, and hypoglycemic potential. All effects were more related to the Lactobacillus and Bifidobacterium genera, associated with more than one property mentioned. CONCLUSION: The mechanisms attributed to the microorganisms suggest the therapeutic potential of probiotics in the non-pharmacological treatment of pain. New applications for probiotics have resulted from great research interest by academia, but also reflect commercial interests despite the paucity of clinical trials. Thus, the present work supports the evolution of research to explore the benefits of probiotics and their clinical use in DN.

The effects of fraxetin and monnieriside A on Cultured L929 fibroblasts.

Skin lesions are considered a public health problem, compromising patients' quality of life. This work aimed to evaluate the effects of fraxetin and monnieriside A on Cultured L929 Fibroblasts through the scratch assay. Supernatants and cells from the fibroblast culture treated with the compounds were used to evaluate essential markers of the tissue repair process (IGF-1, VEGF, IL-8, IL-10, FGF-2, COL1A2, COL4A, PDGF) using ELISA and qRT-PCR. The results showed that fraxetin and MOA were non-cytotoxic and could stimulate cellular migration. Fraxetin induced IGF-1, VEGF, IL-8, and IL-10 expression, while MOA induced FGF2, COL1A2, and IL-10 expression. Altogether, these results set provides evidence that fraxetin and MOA have healing potential for tissue repair, paving the way for in vivo studies and clinical trials to validate the in vitro results.

Mesenchymal stem cells reduce the oxaliplatin-induced sensory neuropathy through the reestablishment of redox homeostasis in the spinal cord.

AIMS: The present study was designed to investigate whether the antinociceptive effect of bone marrow-derived mesenchymal stem/stromal cells (MSC) during oxaliplatin (OXL)-induced sensory neuropathy is related to antioxidant properties. MAIN METHODS: Male mice C57BL/6 were submitted to repeated intravenous administration of OXL (1 mg/kg, 9 administrations). After the establishment of sensory neuropathy, mice were treated with a single intravenous administration of MSC (1 × 106), vehicle or gabapentin. Paw mechanical and thermal nociceptive thresholds were evaluated through von Frey filaments and cold plate test, respectively. Motor performance was evaluated in the rota-rod test. Gene expression profile, cytokine levels, and oxidative stress markers in the spinal cord were evaluated by real-time PCR, ELISA and biochemical assays, respectively. KEY FINDINGS: OXL-treated mice presented behavioral signs of sensory neuropathy, such as mechanical allodynia and thermal hyperalgesia, which were completely reverted by a single administration of MSC. Repeated oral treatment with gabapentin (70 mg/kg) induced only transient antinociception. The IL-1ß and TNF-α spinal levels did not differ between mice with or without sensory neuropathy. MSC increased the levels of anti-inflammatory cytokines, IL-10 and TGF-ß, in the spinal cord of neuropathic mice, in addition to increasing the gene expression of antioxidant factors SOD and Nrf-2. Additionally, nitrite and MDA spinal levels were reduced by the MSC treatment. SIGNIFICANCE: MSC induce reversion of sensory neuropathy induced by OXL possibly by activation of anti-inflammatory and antioxidant pathways, leading to reestablishment of redox homeostasis in the spinal cord.

Physalis angulata concentrated ethanolic extract suppresses nociception and inflammation by modulating cytokines and prostanoids pathways.

Physalins are seco-steroids with a variety of pharmacological activities already described. In this study the pharmacological properties of a standardized concentrated ethanolic extract from Physalis angulata (CEEPA), rich in physalins B, D, F and G, were studied in models of pain and inflammation in mice. Inflammatory mediators were measured by radioimmunoassay and Real-Time PCR in mice paws after the CFA stimuli. Systemic administration of CEEPA produced antinociceptive effect on the writhing test and formalin test. In the writhing test, physalins B, D, F and G showed that the antinociceptive effect of CEEPA is more potent than that of these purified compounds. In addition, CEEPA reduced the levels of TNF-α, IL-1ß, COX-2 and iNOS mRNA in the CFA-induced paw inflammation. Likewise, CEEPA decreased the TNF-α, IL-1ß and PGE2 paw levels. In conclusion, CEEPA induces antinociceptive and anti-inflammatory effects, with improved pharmacological potency relative to pure physalins, associated to modulation of cytokine and cyclooxygenase pathways.

Physalis angulata reduces the progression of chronic experimental periodontitis by immunomodulatory mechanisms.

ETHNOPHARMACOLOGICAL RELEVANCE: Physalis angulata is an herb found in tropical and subtropical regions of the world; it is widely applied in popular medicine due to the therapeutic properties of the whole plant and its parts. Extracts and infusions of this plant have been extensively applied in folk medicine worldwide to treat inflammatory and immune-mediated diseases, including oral inflammatory conditions such as sore throat and gingivitis. AIM OF THE STUDY: The present study was designed to investigate the protective effects of the ethanolic extract of P. angulata (EEPA) in a murine model of chronic periodontitis, aiming to corroborate its traditional use as an anti-inflammatory and immunomodulatory agent, and to point out possible mechanisms involved in these effects. MATERIALS AND METHODS: EEPA was obtained from the stems of P. angulata collected in Belém (PA, Brazil). Chronic periodontitis was induced in male C57BL/6 mice by 12 administrations of lipopolysaccharide (LPS; 20 µg/1µL) into the gingival papilla in the course of 28 days. Starting from the 15th day after the first LPS injection, mice were daily treated with EEPA (50 or 100 mg/kg), nimesulide (25 mg/kg, reference drug), or vehicle by oral route for 14 days. At the end of the experimental period, alveolar bone loss was evaluated along with the gingival expression of biomarkers of periodontitis and cytokines by RT-q-PCR and ELISA. Hematological and biochemical parameters suggestive of systemic toxicity were also evaluated. The transcriptional activity of NF-κB was investigated using the luciferase assay in macrophages. RESULTS: Mice with chronic experimental periodontitis suffered alveolar bone loss that was prevented by the treatment with EEPA (50 or 100 mg/kg) or nimesulide (25 mg/kg). EEPA (50 and 100 mg/kg) and nimesulide (25 mg/kg) reduced mRNA levels of MMP-9 mRNA, but not of TIMP-1 in gingival tissue of periodontitis-induced mice. Both treatments also reduced the production of the pro-inflammatory cytokines IL-1ß and IL-6. The treatment with EEPA (100 mg/kg) increased the production of the anti-inflammatory cytokine TGF-ß. No hematological or biochemical alterations were caused by the daily treatment with EEPA. In vitro luciferase assay suggested that a putative mechanism of EEPA is reducing the transcriptional activity of NF-κB. CONCLUSIONS: EEPA exhibited a disease-modifying effect in the chronic experimental periodontitis, along with unidentifiable systemic toxicity. This work corroborates the traditional use of P. angulata in oral inflammatory conditions and provides mechanistic hypotheses to explain its therapeutic effects.

Essential oils and isolated compounds from Lippia alba leaves and flowers: antimicrobial activity and osteoclast apoptosis.

In the present study, essential oils extracted from the leaves and flowers of Lippia alba (Mill.) N.E.Br. (L. alba) were analyzed for their antimicrobial activity and their effects on osteoclasts. The periodontal pathogens, Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans; ATCC 43717), Fusobacterium nucleatum (F. nucleatum; ATCC 25586) and Porphyromonas gingivalis (P. gingivalis); ATCC 33277) were used in antimicrobial activity assays for determining the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC), whereas Bacteroides fragilis (B. fragilis; ATCC 25285) was used as the control microorganism. Osteoclast (OC) apoptosis was assessed by TUNEL assay and Fas receptor expression was detected by immunocytochemistry. The analysis of antimicrobial activity revealed that P. gingivalis had the lowest MIC values, whereas A. actinomycetemcomitans had the highest. L. alba essential oils were found to be toxic to human cells, although the compounds, carvone, limonene and citral, were non-toxic and induced apoptosis in the OCs. This study demonstrates that L. alba has potential biotechnological application in dentistry. In fact periodontal disease has a multifactorial etiology, and the immune response to microbial challenge leads to osteoclast activation and the resorption of the alveolar bone, resulting in tooth loss.

Atividade antimicrobiana do óleo essencial de Ocimum americanum e Ocimum basilicum sobre periodontopatógenos / Antimicrobial activity of essential oil of Ocimum americanum and Ocimum basilicum against periodontopathogens

Na doença periodontal, a resposta imune ao desafio microbiano resulta em ativação de osteoclastos e reabsorção do osso alveolar, culminando com a perda do dente. Deste modo, a busca por compostos com atividade antimicrobiana torna-se relevante no controle da formação do biofilme dental. Com o crescente aumento da resistência bacteriana aos antimicrobianos, o descobrimento de novas drogas seria uma ferramenta útil e neste cenário as plantas medicinais são alternativas promissoras. No presente estudo a atividade antimicrobiana de óleos essenciais extraídos de folhas e flores de Ocimum americanum e Ocimum basilicum foi avaliada frente aos periodontopatógenos Aggregatibacter actinomycetemcomitans (ATCC 43717), Fusobacterium nucleatum (ATCC 25586), Porphyromonas gingivalis (ATCC 33277) e frente ao micro-organismo Bacteroides fragilis (ATCC 25285). O método de macrodiluição em tubos foi utilizado para determinação da concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM). Foram registrados menores valores de CIM (0,00625 mg.mL-1 a 0,0125 mg.mL-1) frente a bactéria P. gingivalis, sendo os maiores valores ( <3,2 mg.mL-1) registrados para A. actinomycetemcomitans. Estas concentrações foram consideradas bactericidas quando a CBM foi avaliada. A composição química dos óleos mostrou a presença de linalol e metil cinamato, compostos com reconhecida atividade antimicrobiana, o que poderia explicar os resultados encontrados. Este trabalho mostrou que as plantas medicinais do gênero Ocimum estudadas foram capazes de inibir o crescimento microbiano, especialmente de P. gingivalis, apresentando, portanto, potencial biotecnológico para uso na área de odontologia

In Periodontal disease, the immune response to microbial challenge results in osteoclast activation and alveolar bone resorption, leading to tooth loss, so the search for chemical compounds with antimicrobial activity is relevant to control biofilm formation. With the increasing of bacterial resistance to antibiotics, the discovery of new drugs would be a useful tool, and in this scenario the medicinal plants are promising alternatives. In this study, the antimicrobial activity of essential oils extracted from leaves and flowers of Ocimum americanum and Ocimum basilicum was evaluated against the periodontopathogens Aggregatibacter actinomycetemcomitans (ATCC 43717), Fusobacterium nucleatum (ATCC 25586), Porphyromonas gingivalis (ATCC 33277) and against the bacteria Bacteroides fragilis (ATCC 25285). The macrodilution method was used to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). There were recorded lower values of MIC (0.00625 mg.mL-1 to 0.0125 mg.mL-1) against P. gingivalis, and the highest values (<3,2 mg.mL-1) were recorded for A. actinomycetemcomitans. These concentrations were considered bactericidal when MBC was assessed. The chemical composition of the oils showed the presence of linalool and methyl cinnamate, compounds with proven antimicrobial activity, which could explain the results. This project showed that medicinal plants studied were able to inhibit microbial growth, especially against P. gingivalis, presenting therefore biotechnological potential for use in dentistry

Uso de produtos naturais como coadjuvante no tratamento da doença periodontal. [revisão] / Use of natural products as adjuvant in the treatment of periodontal disease. [review]

A doença periodontal (DP) é descrita como um conjunto de processos inflamatórios e infecciosos que acomete os tecidos periodontais, de etiologia multifatorial, localização sítiodependente e considerada pela Organização Mundial de Saúde como uma das duas principais enfermidades de risco para a saúde bucal. Desencadeada e perpetuada por bactérias anaeróbias Gram-negativas, cuja resistência a antibioticoterapia convencional e a antissépticos bucais exigem a busca por novos métodos coadjuvantes ao tratamento clínico (raspagem e alisamento radicular) da DP. Neste enfoque, o uso de produtos naturais poderia ser muito promissor. O objetivo do trabalho foi realizar uma revisão bibliográfica sobre o tema: utilização de produtos naturais no controle químico do crescimento do biofilme dental subgengival. O trabalho mostrou que este novo conceito de tratamento a base de produtos naturais, merece uma atenção especial, desde que o Brasil é detentor de uma rica biodiversidade e já que diversos trabalhos científicos indicam uma atividade antimicrobiana in vitro em ensaios laboratoriais utilizando produtos naturais. Assim, métodos de tratamento da doença periodontal eficazes e acessíveis à população poderiam modificar o quadro atual em que se encontra a saúde bucal dos brasileiros no cenário internacional.

The periodontal disease (PD) is described as a set of inflammatory and infectious process that attacks periodontal tissue of multifactorial etiology, localized and considered by the World Health Organization (WHO) as one of the two main disease in odontology. Unchained and perpetuated for Gram negative anaerobic bacteria, whose anti-septic and antibiotic resistance demand new methods for clinical treatment (scaling and root planing). In this approach, the use of natural products could be promising. The aim of this work was a literature review about the use of natural products in the chemical control of the growth of subgingival dental biofilm. The work showed that antimicrobial natural agents can be useful as adjunct to mechanical therapy and deserve a special attention, since Brazil hold a rich biodiversity and because scientific works indicate an antimicrobial activity in vitro in assays using natural products. Thus, methods of treatment of periodontal diseases, efficient and accessible to Brazilian population could change the actual scenery of odontology in Brazil.

Immunomodulatory and antibacterial activities of extracts from Rutaceae species / Atividade imunomoduladora e antibacteriana de extratos de espécies da família Rutaceae

Rutaceae is a taxon with species very well distributed in Brazilian semi-arid area, commonly used in folk medicine. Species from this genus have diverse biological activity described in literature. In this work, immunomodulatory and bactericidal activity are described for chloroform and ethyl acetate extracts of three of them (Esenbeckia grandiflora Mart., Pilocarpus spicatus A.St.-Hil. and Galipea simplicifolia Schult.). Initially all the samples had their cytotoxicity evaluated, aiming to determine the LC50. The immunomodulatory potential was evaluated in cultures of murine splenocytes stimulated or not with concanavalin A and in a mixed lymphocyte reaction (MLR) using splenocytes from BALB/c (H-2d) mice immunized with splenocytes from C57Bl/6 (H-2b) mice. Four samples had higher values of lymphoproliferation inhibition in concanavalin A-stimulated cultures and were evaluated in MLR. The antibacterial activity of extracts was also evaluated and the minimal inhibitory concentrations (MIC) for two active samples were 1.0 and 5.0 mg/ml for extracts from Esenbeckia grandiflora Mart. and Galipea simplicifolia Schult., respectively. Thus, our results reinforce data of literature relating biological activity for many species of the Rutaceae family and encourage studies with these species aiming to discover active compounds, candidates to new medicines.

A família Rutaceae apresenta espécies vegetais muito bem distribuídas no Semi-Árido Brasileiro e comumente usadas em medicina popular. Espécies dessa família tem diversas atividades biológicas descritas na literatura. Neste trabalho, atividades imunomoduladora e bactericida são descritas para o extrato acetato de etila e clorofórmico de três espécies da família (Esenbeckia grandiflora Mart., Pilocarpus spicatus A.St.-Hil. e Galipea simplicifolia Schult.). Todas as amostras foram inicialmente avaliadas quanto à sua citotoxicidade, com objetivo de determinar a LC50. O potencial imunomodulador foi avaliado em culturas de esplenócitos murinos estimulados ou não com concanavalina A e também em reação mista linfocitária (RML), usando também esplenócitos de camundongos BALB/c (H-2d) imunizados com esplenócitos de camundongos C57Bl/6 (H-2b). Quatro amostras tiveram os mais elevados valores percentuais de inibição da proliferação de linfócitos ativados pela concanavalina A e foram avaliados em RML. A atividade antibacteriana dos extratos foi também avaliada e a concentração mínima inibitória (CMI) para duas amostras ativas foi de 1.0 e 5.0 mg/mL, respectivamente para as espécies Esenbeckia grandiflora Mart. and Galipea simplicifolia Schult. Assim, os dados aqui apresentados reforçam informações da literatura científica relacionados à atividade biológica para muitas espécies da família Rutaceae e incentivam outros estudos com estas visando descobrir substâncias ativas, potenciais candidatas a novos fármacos.

Prevalência de porphyromonas gingivalis. e leucometria, em mestiços brasileiros com periodontite crónica severa / Porphyromonas gingivalis prevalence and leukometry in Brazilians of mixed race with severe chronic periodontitis

Objetívos: Sendo a periodontite uma doença multifatorial que se inicia e é mantida pela agressão das bactérias periodontopatogênicas, este trabalho objetivou identificar a presença de Pgingvalis (Pg) no biofilme subgengival em indivíduos com periodontite crónica severa, bem como avaliar o leucograma respectivo.Material e métodos: Oitenta e quatro voluntários não-fumantes foram selecionados para o estudo: 43 pacientes com periodontite crónica severa (grupo caso - PCS) e 41 indivíduos sem periodontite (grupo controle - NP). Parâmetros clínicos periodontais e o leucograma foram avaliados. Amostras do biofilme subgengival foram coletadas para detecção de Pg pela técnica da reação em cadeia da polimerase (PCR). Para a análise estatística foram usados os testes t-student e Mann-Whitney (p<0.05). Resultados: Foi detectada a presença de Pg no biofilme subgengival de 29 pacientes (67,4%) do grupo PCS, não sendo observado este periodontopatógeno em nenhum dos indivíduos do grupo NP O grupo PCS apresentou significantemente valores mais elevados do que o NP no número de leucócitos totais e no número absoluto de neutrófilos. Conclusões: Os resultados mostraram que na maioria dos pacientes do grupo PCS foi detectada a presença de Porphyromonas gingivalis e que esta infecção bacteriana pode refletir-se na leucometria.