LED therapy modulates M1/M2 macrophage phenotypes and mitigates dystrophic features in treadmill-trained mdx mice.

The mdx mouse phenotype, aggravated by chronic exercise on a treadmill, makes this murine model more reliable for the study of Duchenne muscular dystrophy (DMD) and allows the efficacy of therapeutic interventions to be evaluated. This study aims to investigate the effects of photobiomodulation by light-emitting diode (LED) therapy on functional, biochemical and morphological parameters in treadmill-trained adult mdx animals. Mdx mice were trained for 30 min of treadmill running at a speed of 12 m/min, twice a week for 4 weeks. The LED therapy (850 nm) was applied twice a week to the quadriceps muscle throughout the treadmill running period. LED therapy improved behavioral activity (open field) and muscle function (grip strength and four limb hanging test). Functional benefits correlated with reduced muscle damage; a decrease in the inflammatory process; modulation of the regenerative muscular process and calcium signalling pathways; and a decrease in oxidative stress markers. The striking finding of this work is that LED therapy leads to a shift from the M1 to M2 macrophage phenotype in the treadmill-trained mdx mice, enhancing tissue repair and mitigating the dystrophic features. Our data also imply that the beneficial effects of LED therapy in the dystrophic muscle correlate with the interplay between calcium, oxidative stress and inflammation signalling pathways. Together, these results suggest that photobiomodulation could be a potential adjuvant therapy for dystrophinopathies.

Synthesis and activity of benzimidazole N-Acylhydrazones against Trypanosoma cruzi, Leishmania amazonensis and Leishmania infantum.

In this study, we present the design, synthesis, and cytotoxic evaluation of a series of benzimidazole N-acylhydrazones against strains of T. cruzi (Y and Tulahuen) and Leishmania species (L. amazonensis and L. infantum). Compound (E)-N'-((5-Nitrofuran-2-yl)methylene)-1H-benzo[d]imidazole-2-carbohydrazide demonstrated significant activity against both trypomastigote and amastigote forms (Tulahuen strain), with an IC50/120 h of 0.033 µM and a selectivity index (SI) of 7680. This represents a potency 46 times greater than that of benznidazole (IC50/120 h = 1.520 µM, SI = 1390). Another compound (E)-N'-(2-Hydroxybenzylidene)-1H-benzo[d]imidazole-2-carbohydrazide showed promising activity against both trypomastigote and amastigote forms (Tulahuen strain), with an IC50/120 h of 3.600 µM and an SI of 14.70. However, its efficacy against L. infantum and L. amazonensis was comparatively lower. These findings provide valuable insights for the development of more effective treatments against Trypanosoma cruzi.

Encapsulation of Citrus sinensis essential oil and R-limonene in lipid nanocarriers: A potential strategy for the treatment of leishmaniasis.

Leishmaniases, a group of neglected tropical diseases caused by an intracellular parasite of the genus Leishmania, have significant impacts on global health. Current treatment options are limited due to drug resistance, toxicity, and high cost. This study aimed to develop nanostructured lipid carriers (NLCs) for delivering Citrus sinensis essential oil (CSEO) and its main constituent, R-limonene, against leishmaniasis. The influence of surface-modified NLCs using chitosan was also examined. The NLCs were prepared using a warm microemulsion method, and surface modification with chitosan was achieved through electrostatic interaction. These nanocarriers were characterized by differential scanning calorimetry (DSC), X-ray diffraction (XRD), transmission electron microscopy, and dynamic light scattering (DLS). In vitro cytotoxicity was assessed in L929 and RAW 264.7 cells, and leishmanicidal activity was evaluated against promastigote and amastigote forms. The NLCs were spherical, with particle sizes ranging from 97.9 nm to 111.3 nm. Chitosan-coated NLCs had a positive surface charge, with zeta potential values ranging from 45.8 mV to 59.0 mV. Exposure of L929 cells to NLCs resulted in over 70 % cell viability. Conversely, surface modification significantly reduced the viability of promastigotes (93 %) compared to free compounds. Moreover, chitosan-coated NLCs presented a better IC50 against the amastigote forms than uncoated NLCs. Taken together, these findings demonstrate the feasibility of using NLCs to overcome the limitations of current leishmaniasis treatments, warranting further research.

Drug screening and development cascade for Chagas disease: an update of in vitro and in vivo experimental models.

Chagas disease is a tropical neglected disease that affects millions of people worldwide, still demanding a more effective and safer therapy, especially in its chronic phase which lacks a treatment that promotes substantial parasitological cure. The technical note of Romanha and collaborators published in 2010 aimed establish a guideline with the set of minimum criteria and decision gates for the development of new agents against Trypanosoma cruzi with the focus on developing new antichagasic drugs. In this sense, the present review aims to update this technical note, bringing the state of the art and new advances on this topic in recent years.

Ceftazidime and Usnic Acid Encapsulated in Chitosan-Coated Liposomes for Oral Administration against Colorectal Cancer-Inducing Escherichia coli.

Escherichia coli has been associated with the induction of colorectal cancer (CRC). Thus, combined therapy incorporating usnic acid (UA) and antibiotics such as ceftazidime (CAZ), co-encapsulated in liposomes, could be an alternative. Coating the liposomes with chitosan (Chi) could facilitate the oral administration of this nanocarrier. Liposomes were prepared using the lipid film hydration method, followed by sonication and chitosan coating via the drip technique. Characterization included particle size, polydispersity index, zeta potential, pH, encapsulation efficiency, and physicochemical analyses. The minimum inhibitory concentration and minimum bactericidal concentration were determined against E. coli ATCC 25922, NCTC 13846, and H10407 using the microdilution method. Antibiofilm assays were conducted using the crystal violet method. The liposomes exhibited sizes ranging from 116.5 ± 5.3 to 240.3 ± 3.5 nm and zeta potentials between +16.4 ± 0.6 and +28 ± 0.8 mV. The encapsulation efficiencies were 51.5 ± 0.2% for CAZ and 99.94 ± 0.1% for UA. Lipo-CAZ-Chi and Lipo-UA-Chi exhibited antibacterial activity, inhibited biofilm formation, and preformed biofilms of E. coli. The Lipo-CAZ-UA-Chi and Lipo-CAZ-Chi + Lipo-UA-Chi formulations showed enhanced activities, potentially due to co-encapsulation or combination effects. These findings suggest potential for in vivo oral administration in future antibacterial and antibiofilm therapies against CRC-inducing bacteria.

Trypanosoma cruzi killing and immune response boosting by novel phenoxyhydrazine-thiazole against Chagas disease.

Trypanosoma cruzi (T. cruzi) causes Chagas, which is a neglected tropical disease (NTD). WHO estimates that 6 to 7 million people are infected worldwide. Current treatment is done with benznidazole (BZN), which is very toxic and effective only in the acute phase of the disease. In this work, we designed, synthesized, and characterized thirteen new phenoxyhydrazine-thiazole compounds and applied molecular docking and in vitro methods to investigate cell cytotoxicity, trypanocide activity, nitric oxide (NO) production, cell death, and immunomodulation. We observed a higher predicted affinity of the compounds for the squalene synthase and 14-alpha demethylase enzymes of T. cruzi. Moreover, the compounds displayed a higher predicted affinity for human TLR2 and TLR4, were mildly toxic in vitro for most mammalian cell types tested, and LIZ531 (IC50 2.8 µM) was highly toxic for epimastigotes, LIZ311 (IC50 8.6 µM) for trypomastigotes, and LIZ331 (IC50 1.9 µM) for amastigotes. We observed that LIZ311 (IC50 2.5 µM), LIZ431 (IC50 4.1 µM) and LIZ531 (IC50 5 µM) induced 200 µg/mL of NO and JM14 induced NO production in three different concentrations tested. The compound LIZ331 induced the production of TNF and IL-6. LIZ311 induced the secretion of TNF, IFNγ, IL-2, IL-4, IL-10, and IL-17, cell death by apoptosis, decreased acidic compartment formation, and induced changes in the mitochondrial membrane potential. Taken together, LIZ311 is a promising anti-T. cruzi compound is not toxic to mammalian cells and has increased antiparasitic activity and immunomodulatory properties.

Zein nanoparticles containing ceftazidime and tobramycin: antibacterial activity against Gram-negative bacteria.

Aims: This work describes the encapsulation of ceftazidime and tobramycin in zein nanoparticles (ZNPs) and the characterization of their antibacterial and antibiofilm activities against Gram-negative bacteria. Materials & methods: ZNPs were synthesized by nanoprecipitation. Cytotoxicity was assessed by MTT assay and antibacterial and antibiofilm assays were performed by broth microdilution and violet crystal techniques. Results: ZNPs containing ceftazidime (CAZ-ZNPs) and tobramycin (TOB-ZNPs) showed drug encapsulation and thermal stability. Encapsulation of the drugs reduced their cytotoxicity 9-25-fold. Antibacterial activity, inhibition and eradication of biofilm by CAZ-ZNPs and TOB-ZNPs were observed. There was potentiation when CAZ-ZNPs and TOB-ZNPs were combined. Conclusion: CAZ-ZNPs and TOB-ZNPs present ideal physical characteristics for in vivo studies of antibacterial and antibiofilm activities.

A nanotechnology product was developed to treat diseases caused by bacteria. This prototype showed the ideal characteristics and could be administered by ingestion through the mouth, aspiration through the nose or injection into the veins. The prototype did not harm or kill human cells. It killed the bacteria and prevented the formation of a type of protection against antibiotics that bacteria can produce, called a biofilm. Nanotechnology products are a promising alternative for the treatment of bacterial infections.

LEDT and Idebenone treatment modulate autophagy and improve regenerative capacity in the dystrophic muscle through an AMPK-pathway.

PURPOSE: Considering the difficulties and challenges in Duchenne muscular dystrophy (DMD) treatment, such as the adverse effects of glucocorticoids, which are the main medical prescription used by dystrophic patients, new treatment concepts for dystrophic therapy are very necessary. Thus, in this study, we explore the effects of photobiomodulation (PBM; a non-invasive therapy) and Idebenone (IDE) treatment (a potent antioxidant), applied alone or in association, in dystrophic muscle cells and the quadriceps muscle, with special focus on autophagy and regenerative pathways. METHODS: For the in vitro studies, the dystrophic primary muscle cells received 0.5J LEDT and 0.06µM IDE; and for the in vivo studies, the dystrophic quadriceps muscle received 3J LEDT and the mdx mice were treated with 200mg/kg IDE. RESULTS: LEDT and IDE treatment modulate autophagy by increasing autophagy markers (SQSTM1/p62, Beclin and Parkin) and signaling pathways (AMPK and TGF-ß). Concomitantly, the treatments prevented muscle degeneration by reducing the number of IgG-positive fibers and the fibers with a central nucleus; decreasing the fibrotic area; up-regulating the myogenin and MCH-slow levels; and down-regulating the MyoD and MHC-fast levels. CONCLUSION: These results suggest that LEDT and IDE treatments enhance autophagy and prevented muscle degeneration in the dystrophic muscle of the experimental model. These findings illustrate the potential efficacy of LEDT and IDE treatment as an alternative therapy focused on muscle recovery in the dystrophic patient.

Staphylococcus capitis Bloodstream Isolates: Investigation of Clonal Relationship, Resistance Profile, Virulence and Biofilm Formation.

Staphylococcus capitis has been recognized as a relevant opportunistic pathogen, particularly its persistence in neonatal ICUs around the world. Therefore, the aim of this study was to describe the epidemiological profile of clinical isolates of S. capitis and to characterize the factors involved in the persistence and pathogenesis of these strains isolated from blood cultures collected in a hospital in the interior of the state of São Paulo, Brazil. A total of 141 S. capitis strains were submitted to detection of the mecA gene and SCCmec typing by multiplex PCR. Genes involved in biofilm production and genes encoding enterotoxins and hemolysins were detected by conventional PCR. Biofilm formation was evaluated by the polystyrene plate adherence test and phenotypic resistance was investigated by the disk diffusion method. Finally, pulsed-field gel electrophoresis (PFGE) was used to analyze the clonal relationship between isolates. The mecA gene was detected in 99 (70.2%) isolates, with this percentage reaching 100% in the neonatal ICU. SCCmec type III was the most prevalent type, detected in 31 (31.3%) isolates and co-occurrence of SCCmec was also observed. In vitro biofilm formation was detected in 46 (32.6%) isolates but was not correlated with the presence of the ica operon genes. Furthermore, biofilm production in ICU isolates was favored by hyperosmotic conditions, which are common in ICUs because of the frequent parenteral nutrition. Analysis of the clonal relationship between the isolates investigated in the present study confirms a homogeneous profile of S. capitis and the persistence of clones that are prevalent in the neonatal ICU and disseminated across the hospital. This study highlights the adaptation of isolates to specific hospital environments and their high clonality.

Synthesis of hydrazinyl-thiazole ester derivatives, in vitro trypanocidal and leishmanicidal activities.

Aim: To synthesize novel more potent trypanocidal and leishmanicidal agents. Methods: Hantzsch's synthetic strategy was used to synthesize 1,3-thiazole-4-carboxylates and their N-benzylated derivatives. Results: 28 new thiazole-carboxylates and their N-benzylated derivatives were established to test their trypanocidal and leishmanicidal activities. From both series, compounds 3b, 4f, 4g, 4j and 4n exhibited a better or comparable trypanocidal profile to benznidazole. Among all tested compounds, 4n was found to be the most potent and was better than benznidazole. Conclusion: Further variation of substituents around 1,3-thiazole-4-carboxylates and or hydrazinyl moiety may assist in establishing better and more potent trypanocidal and leishmanicidal agents.

Chagas disease and leishmaniasis are neglected tropical diseases. Herein, 28 1,3-thiazoles have been synthesized from thiosemicarbazones in a rapid, efficient and cost-effective manner. In vitro assays were performed against intracellular amastigotes of Trypanosoma cruzi (T. cruzi) and promastigotes and intracellular amastigote forms of Leishmania infantum (L. infantum) and Leishmania amazonensis (L. amazonensis). Some of the 1,3-thiazole-4-carboxylates inhibited the amastigote form of T. cruzi without affecting macrophage viability, compound 4n being the most potent and better than benznidazole. Our synthesized compounds exhibited promising activity against T. cruzi, thus broadening options for scaffold and lead compound optimization. Concerning the leishmanicidal activity, compound 4g was the best prototype in terms of potency and selectivity. Compounds 4g and 3m showed moderate selectivity and potency against intracellular amastigotes of L. amazonensis and L. infantum, respectively.

Drug screening and development cascade for Chagas disease: an update of in vitro and in vivo experimental models

Chagas disease is a tropical neglected disease that affects millions of people worldwide, still demanding a more effective and safer therapy, especially in its chronic phase which lacks a treatment that promotes substantial parasitological cure. The technical note of Romanha and collaborators published in 2010 aimed establish a guideline with the set of minimum criteria and decision gates for the development of new agents against Trypanosoma cruzi with the focus on developing new antichagasic drugs. In this sense, the present review aims to update this technical note, bringing the state of the art and new advances on this topic in recent years.

Molecular Mimicry between SARS-CoV-2 Proteins and Human Self-Antigens Related with Autoimmune Central Nervous System (CNS) Disorders.

SARS-CoV-2 can trigger autoimmune central nervous system (CNS) diseases in genetically susceptible individuals, a mechanism poorly understood. Molecular mimicry (MM) has been identified in other viral diseases as potential triggers of autoimmune CNS events. This study investigated if MM is the process through which SARS-CoV-2 induces the breakdown of immune tolerance. The frequency of autoimmune CNS disorders was evaluated in a prospective cohort with patients admitted to the COVID-19 Intense Care Unity (ICU) in Rio de Janeiro. Then, an in silico analysis was performed to identify the conserved regions that share a high identity between SARS-CoV-2 antigens and human proteins. The sequences with significant identity and antigenic properties were then assessed for their binding capacity to HLA subtypes. Of the 112 patients included, 3 were classified as having an autoimmune disorder. A total of eleven combinations had significant linear and three-dimensional overlap. NMDAR1, MOG, and MPO were the self-antigens with more significant combinations, followed by GAD65. All sequences presented at least one epitope with strong or intermediate binding capacity to the HLA subtypes selected. This study underscores the possibility that CNS autoimmune attacks observed in COVID-19 patients, including those in our population, could be driven by MM in genetically predisposed individuals.

Evaluation of Proinflammatory Chemokines in HIV Patients with Asymptomatic Leishmania Infantum Infection.

Asymptomatic Leishmania infantum, when associated with HIV, can become severe and potentially fatal. In this co-infection, the worst prognosis may be influenced by the host's immunological aspects, which are crucial in determining susceptibility. Chemokines play an important role in this process by influencing the cellular composition at affected sites and impacting the disease's outcome. Therefore, the aim of this study was to evaluate proinflammatory chemokines in HIV patients with the asymptomatic L. infantum infection. In this cross-sectional study, the levels of CCL2, CCL5, CXCL8, MIG, and IP-10 were measured in 160 serum samples from co-infected patients (n = 53), patients with HIV (n = 90), and negative controls (n = 17). Quantification was determined by flow cytometry. The obtained data were statistically analyzed using the Kruskal-Wallis test, followed by the Dunn's post-test and the Spearman's correlation coefficient. Significance was set at p < 0.05. The chemokines CCL2, CCL5, MIG, and IP-10 exhibited higher levels in the HIV group compared to co-infection. However, the elevated levels of all these chemokines and their increased connectivity in co-infected patients appear to be important in identifying proinflammatory immune responses associated with the asymptomatic condition. Furthermore, a weak negative correlation was observed between higher levels of CXCL8 and lower viral loads in co-infected patients.

Antifungal efficacy of imidazo[1,2-a]pyrazine-based thiosemicarbazones and thiazolidinediones against Sporothrix species.

Aim: To evaluate antifungal potential of 5,6,7,8-tetrahydroimidazo[1,2-a]pyrazine hybrids based on thiosemicarbazones and thiazolidinediones against pathogenic Sporothrix species. Methods: Antifungal activity of nine compounds were assessed by broth microdilution. Interactions between active compounds and itraconazole were evaluated by the checkerboard assay using non-wild-type isolates. Cytotoxicity of the compounds was determined. Results: Four C-3 substituted analogs showed antifungal activity, unrelated to thiosemicarbazone or thiazolidinedione functions. Synergistic interactions between the four compounds and itraconazole, and low toxicity on mouse fibroblast cells were observed. Activity of 5,6,7,8-tetrahydroimidazo[1,2-a]pyrazine hybrids against Sporothrix depended on the substitution on the imidazopyrazine ring. Conclusion: Antifungal potential, overcoming itraconazole resistance and low toxicity indicate the possible use of that series of compounds in a therapeutic alternative for treatment of sporotrichosis.

Orange juice containing Pediococcus acidilactici CE51 modulates the intestinal microbiota and reduces induced inflammation in a murine model of colitis.

The management of inflammatory bowel diseases has been widely investigated, especially ulcerative colitis. Thus, studies with the application of new probiotic products are needed in the prevention/treatment of these clinical conditions. The objective of this work was to evaluate the effects of probiotic orange juice containing Pediococcus acidilactici CE51 in a murine model of colitis. 45 male Swiss lineage mice were used, divided into five groups (n = 9): control, colitis, colitis + probiotic (probiotic orange juice containing CE51), colitis + placebo (orange juice) and colitis + sulfasalazine (10 mg/kg/Weight). The induction of colitis was performed with dextran sodium sulfate (3%). The treatment time was 5 and 15 days after induction. Histopathological analysis, serum measurements of TNF-α and C-reactive protein and metagenomic analysis of feces were performed after euthanasia. Probiotic treatment reduced inflammation in the small intestine, large intestine and spleen. The probiotic did not alter the serum dosages of TNF-α and C-reactive protein. Their use maintained the quantitative ratio of the phylum Firmicutes/Bacteroidetes and increased Lactobacillus helveticus with 15 days of treatment (p < 0.05). The probiotic orange juice containing P. acidilactici CE51 positively modulated the gut microbiota composition and attenuated the inflammation induced in colitis.

IgM antibody responses against Plasmodium antigens in neotropical primates in the Brazilian Atlantic Forest.

Introduction: Zoonotic transmission is a challenge for the control and elimination of malaria. It has been recorded in the Atlantic Forest, outside the Amazon which is the endemic region in Brazil. However, only very few studies have assessed the antibody response, especially of IgM antibodies, in Neotropical primates (NP). Therefore, in order to contribute to a better understanding of the immune response in different hosts and facilitate the identification of potential reservoirs, in this study, naturally acquired IgM antibody responses against Plasmodium antigens were evaluated, for the first time, in NP from the Atlantic Forest. Methods: The study was carried out using 154 NP samples from three different areas of the Atlantic Forest. IgM antibodies against peptides of the circumsporozoite protein (CSP) from different Plasmodium species and different erythrocytic stage antigens were detected by ELISA. Results: Fifty-nine percent of NP had IgM antibodies against at least one CSP peptide and 87% against at least one Plasmodium vivax erythrocytic stage antigen. Levels of antibodies against PvAMA-1 were the highest compared to the other antigens. All families of NP showed IgM antibodies against CSP peptides, and, most strikingly, against erythrocytic stage antigens. Generalized linear models demonstrated that IgM positivity against PvCSP and PvAMA-1 was associated with PCR-detectable blood-stage malaria infection and the host being free-living. Interestingly, animals with IgM against both PvCSP and PvAMA-1 were 4.7 times more likely to be PCR positive than animals that did not have IgM for these two antigens simultaneously. Discussion: IgM antibodies against different Plasmodium spp. antigens are present in NP from the Atlantic Forest. High seroprevalence and antibody levels against blood-stage antigens were observed, which had a significant association with molecular evidence of infection. IgM antibodies against CSP and AMA-1 may be used as a potential marker for the identification of NP infected with Plasmodium, which are reservoirs of malaria in the Brazilian Atlantic Forest.

Influence of natalizumab on resting-state connectivity in patients with multiple sclerosis.

Background: Changes in brain connectivity occur in patients with multiple sclerosis (MS), even in patients under disease-modifying therapies. Using magnetic resonance imaging (MRI) to asses patients treated with disease-modifying therapies, such as natalizumab, can elucidate the mechanisms involved in clinical deterioration in MS. Objectives: To evaluate differences in resting-state functional connectivity among MS patients treated with natalizumab, MS patients not treated with natalizumab, and controls. Design: Single-center retrospective cross-sectional study. Methods: Twenty-three MS patients being treated with natalizumab were retrospectively compared with 23 MS patients who were naïve for natalizumab, and were using first-line medications (interferon-ß and/or glatiramer acetate), and 17 gender- and age-matched control subjects. The MS patient groups were also matched for time since diagnosis and hyperintense lesion volume on FLAIR. All participants underwent brain MRI using a 3 Tesla scanner. Independent component analysis and dual regression were used to identify resting-state functional connectivity using the FMRIB Software Library. Results: In comparison to controls, the MS patients treated with natalizumab presented decreased connectivity in the left orbitofrontal cortex, in the anterior cingulate and orbitofrontal cortex network. The patients not treated with natalizumab presented increased connectivity in the secondary visual, sensorimotor, and ventral attention networks in comparison to controls.Compared to patients treated with natalizumab, the patients not using natalizumab presented increased connectivity in the left Heschl's gyrus and in the right superior frontal gyrus in the ventral attention network. Conclusion: Differences in brain connectivity between MS patients not treated with natalizumab, healthy controls, and patients treated with natalizumab may be secondary to suboptimal neuronal compensation due to prior less efficient treatments, or due to a compensation in response to maladaptive plasticity.

LED therapy plus idebenone treatment targeting calcium and mitochondrial signaling pathways in dystrophic muscle cells.

Intracellular calcium dysregulation, oxidative stress, and mitochondrial dysfunction are some of the main pathway contributors towards disease progression in Duchenne muscular dystrophy (DMD). This study is aimed at investigating the effects of light emitting diode therapy (LEDT) and idebenone antioxidant treatment, applied alone or together in dystrophic primary muscle cells from mdx mice, the experimental model of DMD. Mdx primary muscle cells were submitted to LEDT and idebenone treatment and evaluated for cytotoxic effects and calcium and mitochondrial signaling pathways. LEDT and idebenone treatment showed no cytotoxic effects on the dystrophic muscle cells. Regarding the calcium pathways, after LEDT and idebenone treatment, a significant reduction in intracellular calcium content, calpain-1, calsequestrin, and sarcolipin levels, was observed. In addition, a significant reduction in oxidative stress level markers, such as H2O2, and 4-HNE levels, was observed. Regarding mitochondrial signaling pathways, a significant increase in oxidative capacity (by OCR and OXPHOS levels) was observed. In addition, the PGC-1α, SIRT-1, and PPARδ levels were significantly higher in the LEDT plus idebenone treated-dystrophic muscle cells. Together, the findings suggest that LEDT and idebenone treatment, alone or in conjunction, can modulate the calcium and mitochondrial signaling pathways, such as SLN, SERCA 1, and PGC-1α, contributing towards the improvement of the dystrophic phenotype in mdx muscle cells. In addition, data from the LEDT plus idebenone treatment showed slightly better results than those of each separate treatment in terms of SLN, OXPHOS, and SIRT-1.

In vitro evaluation of antioxidant, cytotoxic, trypanocidal and antimicrobial activities of lignin obtained from Caesalpinia ferrea leaves and its use as an excipient in the release of oxacillin and fluconazole.

In this context, the objective of this work was to isolate an alkaline lignin from the leaves of C. ferrea, in addition to investigating different biological activities and its use in the production of releasing tablets in vitro. Initially, the analysis of the composition of the leaves was performed, the contents were: cellulose (33.09 ± 0.3 %), hemicellulose (25.13 ± 0.1 %), lignin (18.29 ± 0.1 %), extractives (17.28 ± 1.0 %) and ash (6.20 ± 0.1 %). The leaves were fractionated to obtain alkaline lignin. The yield of obtaining lignin was 80.12 ± 0.1 %. The obtained lignin was characterized by the techniques: elemental analysis, FTIR, UV/Vis, 2D-NMR, GPC, TGA/DTG, DSC and PY-GC/MS. The results showed that the lignin obtained is of the GSH type, of low molecular weight and thermally stable. The in vitro antioxidant activity was evaluated by different assays promoting results only for DPPH (559.9 ± 0.8 µg/mL) and ABTS (484.1 ± 0.1 µg/mL) being able to promote low antioxidant activity. In addition, it showed low cytotoxicity in normal mammalian cells and promising antitumor and trypanocidal activity. Regarding antimicrobial activity, it was able to inhibit the growth of a strain of Staphylococcus aureus resistant to methicillin, presenting MIC values equal to the standard antibiotic oxacillin. It was also able to inhibit a strain of Candida albicans HAM13 sensitive to fluconazole. In addition, lignin promoted a synergistic effect by promoting a decrease in MIC against these two strains evaluated. Finally, lignin proved to be an excipient with potential for controlled release of antimicrobials.

In vitro bioevaluation and docking study of dihydrosphingosine and ethambutol analogues against sensitive and multi-drug resistant Mycobacterium tuberculosis.

Tuberculosis remains a major public health problem and one of the top ten causes of death worldwide. The alarming increase in multidrug-resistant and extensively resistant variants (MDR, pre-XDR, and XDR) makes the disease more difficult to treat and control. New drugs that act against MDR/XDR strains are needed for programs to contain this major epidemic. The present study aimed to evaluate new compounds related to dihydro-sphingosine and ethambutol against sensitive and pre-XDR Mycobacterium strains, as well as to characterize the pharmacological activity through in vitro and in silico approaches in mmpL3 protein. Of the 48 compounds analyzed, 11 demonstrated good to moderate activity on sensitive and MDR Mycobacterium tuberculosis (Mtb), with a Minimum Inhibitory Concentration (MIC) ranging from 1.5 to 8 µM. They presented 2 to 14 times greater potency of activity when compared to ethambutol in pre-XDR strain, and demonstrated a selectivity index varying between 2.21 and 82.17. The substance 12b when combined with rifampicin, showed a synergistic effect (FICI = 0.5) on sensitive and MDR Mtb. It has also been shown to have a concentration-dependent intracellular bactericidal effect, and a time-dependent bactericidal effect in M. smegmatis and pre-XDR M. tuberculosis. The binding mode of the compounds in its cavity was identified through molecular docking and using a predicted structural model of mmpL3. Finally, we observed by transmission electron microscopy the induction of damage to the cell wall integrity of M. tuberculosis treated with the substance 12b. With these findings, we demonstrate the potential of a 2-aminoalkanol derivative to be a prototype substance and candidate for further optimization of molecular structure and anti-tubercular activity in preclinical studies.