Immune response of BALB/c mice infected with two strains of Corynebacterium pseudotuberculosis.

This work evaluated aspects of the immune response of BALB/c mice infected with Corynebacterium pseudotuberculosis (T1 and C57). The fifteen BALB/c mice were euthanized after 70 days of infection and morphologically evaluated, also analyzing the innate and adaptive immune responses. The C57 strain induced more pronounced morphological changes than the T1 strain. There was an increase in CD4+ and CD8+ T cells identified during infection with the C57 strain. Cytokines of the inflammatory profile IL-1α and IL-6 and regulatory IL-13 and IL-10 presented significant differences. Cytokines IL-2, IL-4, INF-γ, IL-22, IL-21, and IL-27 did not differ significantly between groups. The obtained results contribute to a better understanding of the type of response and the immunological mechanisms involved during infection with different strains of C. pseudotuberculosis.

Contribution of parasite and host genotype to immunopathology of schistosome infections.

BACKGROUND: The role of pathogen genotype in determining disease severity and immunopathology has been studied intensively in microbial pathogens including bacteria, fungi, protozoa and viruses but is poorly understood in parasitic helminths. The medically important blood fluke Schistosoma mansoni is an excellent model system to study the impact of helminth genetic variation on immunopathology. Our laboratory has demonstrated that laboratory schistosome populations differ in sporocyst growth and cercarial production in the intermediate snail host and worm establishment and fecundity in the vertebrate host. Here, we (i) investigate the hypothesis that schistosome genotype plays a significant role in immunopathology and related parasite life history traits in the vertebrate mouse host and (ii) quantify the relative impact of parasite and host genetics on infection outcomes. METHODS: We infected BALB/c and C57BL/6 mice with four different laboratory schistosome populations from Africa and the Americas. We quantified disease progression in the vertebrate host by measuring body weight and complete blood count (CBC) with differential over a 12-week infection period. On sacrifice, we assessed parasitological (egg and worm counts, fecundity), immunopathological (organ measurements and histopathology) and immunological (CBC with differential and cytokine profiles) characteristics to determine the impact of parasite and host genetics. RESULTS: We found significant variation between parasite populations in worm numbers, fecundity, liver and intestine egg counts, liver and spleen weight, and fibrotic area but not in granuloma size. Variation in organ weight was explained by egg burden and intrinsic parasite factors independent of egg burden. We found significant variation between infected mouse lines in cytokine levels (IFN-γ, TNF-α), eosinophils, lymphocytes and monocyte counts. CONCLUSIONS: This study showed that both parasite and host genotype impact the outcome of infection. While host genotype explains most of the variation in immunological traits, parasite genotype explains most of the variation in parasitological traits, and both host and parasite genotypes impact immunopathology outcomes.

Lactobacillus gasseri BNR17 Ameliorates Dexamethasone-Induced Muscle Loss in BALB/c Mice and C2C12 Myotubes.

This study aimed to investigate the effects and mechanism of Lactobacillus gasseri BNR17, a probiotic strain isolated from human breast milk, on dexamethasone-induced muscle loss in mice and cultured myotubes. BALB/c mice were intraperitoneally injected with dexamethasone, and orally administered L. gasseri BNR17 for 21 days. L. gasseri BNR17 treatment ameliorated dexamethasone-induced decline in muscle function, as evidenced by an increase in forelimb grip strength, treadmill running time, and rotarod retention time in both female and male mice. In addition, L. gasseri BNR17 treatment significantly increased the mass of the gastrocnemius and quadriceps muscles. Dual-energy X-ray absorptiometry showed a significant increase in lean body mass and a decrease in fat mass in both whole body and hind limb after treatment with L. gasseri BNR17. It was found that L. gasseri BNR17 treatment downregulated serum myostatin level and the protein degradation pathway composed of muscle-specific ubiquitin E3 ligases, MuRF1 and MAFbx, and their transcription factor FoxO3. In contrast, L. gasseri BNR17 treatment upregulated serum insulin-like growth factor-1 level and Akt-mTOR-p70S6K signaling pathway involved in protein synthesis in muscle. As a result, L. gasseri BNR17 treatment significantly increased the levels of major muscular proteins such as myosin heavy chain and myoblast determination protein 1. Consistent with in vivo results, L. gasseri BNR17 culture supernatant significantly ameliorated dexamethasone-induced C2C12 myotube atrophy in vitro. In conclusion, L. gasseri BNR17 ameliorates muscle loss by downregulating the protein degradation pathway and upregulating the protein synthesis pathway.

Development of a Mouse-Adapted Reporter SARS-CoV-2 as a Tool for Two-Photon In Vivo Imaging.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) often causes severe viral pneumonia. Although many studies using mouse models have examined the pathogenicity of SARS-CoV-2, COVID-19 pathogenesis remains poorly understood. In vivo imaging analysis using two-photon excitation microscopy (TPEM) is useful for elucidating the pathology of COVID-19, providing pathological insights that are not available from conventional histological analysis. However, there is no reporter SARS-CoV-2 that demonstrates pathogenicity in C57BL/6 mice and emits sufficient light intensity for two-photon in vivo imaging. Here, we generated a mouse-adapted strain of SARS-CoV-2 (named MASCV2-p25) and demonstrated its efficient replication in the lungs of C57BL/6 mice, causing fatal pneumonia. Histopathologic analysis revealed the severe inflammation and infiltration of immune cells in the lungs of MASCV2-p25-infected C57BL/6 mice, not unlike that observed in COVID-19 patients with severe pneumonia. Subsequently, we generated a mouse-adapted reporter SARS-CoV-2 (named MASCV-Venus-p9) by inserting the fluorescent protein-encoding gene Venus into MASCV2-p25 and sequential lung-to-lung passages in C57BL/6 mice. C57BL/6 mice infected with MASCV2-Venus-p9 exhibited severe pneumonia. In addition, the TPEM of the lungs of the infected C57BL/6J mice showed that the infected cells emitted sufficient levels of fluorescence for easy observation. These findings suggest that MASCV2-Venus-p9 will be useful for two-photon in vivo imaging studies of the pathogenesis of severe COVID-19 pneumonia.

Heat/non-heat treatment alleviates ß-conglycinin-triggered food allergy reactions by modulating the Th1/Th2 immune balance in a BALB/c mouse model.

BACKGROUND: With the increasing popularity of plant protein-based diets, soy proteins are favored as the most important source of plant protein worldwide. However, potential food allergy risks limit their use in the food industry. This work aims to reveal the mechanism of ß-conglycinin-induced food allergy, and to explore the regulatory mechanism of heat treatment and high hydrostatic pressure (HHP) treatment in a BALB/c mouse model. RESULTS: Our results showed that oral administration of ß-conglycinin induced severe allergic symptoms in BALB/c mice, but these symptoms were effectively alleviated through heat treatment and HHP treatment. Moreover, ß-conglycinin stimulated lymphocyte proliferation and differentiation; a large number of cytokines interleukin (IL)-4, IL-5, IL-10, IL-12 and IL-13 were released and interferon γ secretion was inhibited, which disrupted the Th1/Th2 immune balance and promoted the differentiation and proliferation of naive T cells into Th2-type cells. CONCLUSION: Heat/non-heat treatment altered the conformation of soybean protein, which significantly reduced allergic reactions in mice. This regulatory mechanism may be associated with Th1/Th2 immune balance. Our results provide data support for understanding the changes in allergenicity of soybean protein within the food industry. © 2024 Society of Chemical Industry.

Antimalarial Effects of Nano Chloroquine Loaded Curcumin In vivo.

BACKGROUND: Malaria is still the deadliest parasitic disease caused by Plasmodium spp. Due to drug resistance and their unpleasant side effects, of conventional researchers are enormously seeking to achieve antimalarial drugs with more curative effective, less toxic and cost-affordable drugs using more advanced technology such as nanodrugs. PURPOSE: The present study aimed to examine the antimalarial effects of a novel synthesized nonochloroquine-loaded curcumin relying on dendrimer G2 in susceptible mice. METHODS: Antimalarial activity and toxicity of the nanocomposite were examined on BALB/C mice with microscopy, checking RBCs morphology and related enzymatic activity rate. RESULTS: The maximum inhibitory effect of the nanocomposite was seen at 10 mg/kg, killing 98% of P. berghei compared to sole chloroquine, whereas ED50 was reported at 5.5 mg/kg. The safety of the synthesized nanocomposite was confirmed with biochemical tests with no detrimental effects on mice. The sustainability and longevity of the nanodrug increased significantly with the NDC-CQ assay compared to the control groups. CONCLUSION: The study showed that nonochloroquine-loaded curcumin had a promising inhibitory effect on P. berghei growth in infected mice compared to standard drugs. However, further studies and clinical trials with large samples are recommended to study different aspects of using nanodrug.

Invitro and Invivo Analysis of Human Milk Lactic Acid Bacteria Isolates for Their Anti-hypercholesterolemia Actions.

The aim of this study was to evaluate the cholesterol lowering ability of Lactic Acid Bacteria (LAB) isolated from human breast milk under in vitro and in vivo conditions. Six LAB isolates namely Lacticaseibacillus casei 1A, Lactobacillus gasseri 5A, Enterococcus faecium 2C, Limosilactobacillus fermentum 3D, Pediococcus acidilactici 1C, and Lactiplantibacillus plantarum 7A, were examined for their bile resistance, bile salt hydrolase activity, cholesterol assimilation and viability in cholesterol rich; DeMan Rogosa and Sharpe broth, simulated gastric, small and upper intestinal conditions. During in vivo experiments, two putative LAB isolates were orally gavage to BALB/c mice, fed with normal basal and cholesterol rich (HCD) diets, daily for a period of 4 weeks. Blood serum analysis including total serum cholesterol, triglycerides, high-density and low-density lipoprotein (LDL) cholesterol levels and total fecal LAB counts of the animals were determined. The isolates in study showed bile resistance and bile salt hydrolysis activity, while significant differences (P < 0.05) were seen in their cholesterol assimilation ability. L. gasseri 5A (195.67%) and L. plantarum 7A (193.78%) displayed highest cholesterol removal percentages, respectively. Animals in HCD, fed with L. gasseri 5A and L. plantarum 7A showed decreased levels of total cholesterol and LDL, compared to the control groups. In HCD group liver weight was increased, while fecal LAB counts were decreased. No changes were observed in behavior or body weight in all experimental groups. In conclusion, L. gasseri 5A and L. plantarum 7A isolated from human breast milk demonstrates significant hypocholesterolaemic actions in vitro and in vivo and might be considered a promising candidates for preventing hypercholesterolemia in man and animals.

Strain specific differences in vitamin D3 response: impact on gut homeostasis.

Vitamin D3 regulates a variety of biological processes irrespective of its well-known importance for calcium metabolism. Epidemiological and animal studies indicate a role in immune regulation, intestinal barrier function and microbiome diversity. Here, we analyzed the impact of different vitamin D3- containing diets on C57BL/6 and BALB/c mice, with a particular focus on gut homeostasis and also investigated effects on immune cells in vitro. Weak regulatory effects were detected on murine T cells. By trend, the active vitamin D3 metabolite 1,25-dihydroxyvitamin D3 suppressed IFN, GM-CSF and IL-10 cytokine secretion in T cells of C57BL/6 but not BALB/c mice, respectively. Using different vitamin D3-fortified diets, we found a tissue-specific enrichment of mainly CD11b+ myeloid cells but not T cells in both mouse strains e.g. in spleen and Peyer's Patches. Mucin Reg3γ and Batf expression, as well as important proteins for gut homeostasis, were significantly suppressed in the small intestine of C57BL76 but not BALB/c mice fed with a high-vitamin D3 containing diet. Differences between both mouse stains were not completely explained by differences in vitamin D3 receptor expression which was strongly expressed in epithelial cells of both strains. Finally, we analyzed gut microbiome and again an impact of vitamin D3 was detected in C57BL76 but not BALB/c. Our data suggest strain-specific differences in vitamin D3 responsiveness under steady state conditions which may have important implications when choosing a murine disease model to study vitamin D3 effects.

Letrozole delays acquisition of water maze task in female BALB/c mice: Possible involvement of anxiety.

Letrozole, an aromatase inhibitor preventing estrogen synthesis from testosterone, is used as an adjuvant therapy in estrogen receptor-positive breast cancer patients. However, like other aromatase inhibitors, it induces many side effects, including impaired cognition. Despite its negative effect in humans, results from animal models are inconsistent and suggest that letrozole can either impair or improve cognition. Here, we studied the effects of chronic letrozole treatment on cognitive behavior of adult female BALB/c mice, a relevant animal model for breast cancer studies, to develop an appropriate animal model aimed at testing therapies to mitigate side effects of letrozole. In Morris water maze, letrozole 0.1 mg/kg impaired reference learning and memory. Interestingly, most of the letrozole 0.1 mg/kg-treated mice were able to learn the new platform position in reversal training and performed similar to control mice in a reversal probe test. Results of the reversal test suggest that letrozole did not completely disrupt spatial navigation, but rather delayed acquisition of spatial information. The delay might be related to increased anxiety as suggested by increased thigmotactic behavior during the reference memory training. The learning impairment was water maze-specific since we did not observe impairment in other spatial tasks such as in Y-maze or object location test. In contrast, the dose of 0.3 mg/kg did not have effect on water maze learning and facilitated locomotor habituation and recognition in novel object recognition test. The current study shows that letrozole dose-dependently modulates behavioral response and that its effects are task-dependent.

Development of a hydrogel containing bisabolol-loaded nanocapsules for the treatment of atopic dermatitis in a Balb/c mice model.

α-Bisabolol (αBIS), a plant-derived compound with anti-inflammatory properties, is potentially a therapeutic agent for Atopic dermatitis. However, its poor water solubility and photoinstability limit its topical application. Therefore, the present study, aimed to develop cationic polymeric nanocapsules of αBIS to improve its skin delivery, photostability, and therapeutic efficacy. The αBIS-loaded nanocapsules were prepared using the solvent displacement technique. A Box-Behnken (BB) design was employed to statistically optimize formulation variables and αBIS-loaded nanocapsules characterized by particle size, surface charge and encapsulation efficiency. The optimal formulation was selected, and the spherical shape of the nanocapsules was confirmed by scanning electron microscopy (SEM). Furthermore, hydrogel containing αBIS-loaded nanocapsules was prepared by thickening of nanocapsule suspension with Carbopol 934 and evaluated for rheology, in vitro drug release and skin permeation. Furthermore, a mice model of atopic dermatitis was used to evaluate the anti-inflammatory potential of the hydrogels. The optimal formulation displayed a spherical morphology under scanning electron microscopy (SEM) with an optimum particle size of 133.00 nm, polydispersity index (PDI) of 0.12, high EE% of 93 %, and improved optical stability of αBIS in the prepared nanocapsules compared to the free drug. The nano-based hydrogels demonstrated non-Newtonian pseudoplastic behavior and an increased αBIS in vitro release profile without causing skin irritation in rabbits. Drug retention within the dermis and epidermis layers significantly surpassed that of drug-free hydrogel. Moreover, in vivo histopathological studies and myeloperoxidase (MPO) enzyme activity, revealed that hydrogel containing bisabolol nanocapsules exhibited The best anti-inflammatory effect. The results showed that hydrogels containing bisabolol nanocapsules markedly alleviated dermatitis-related inflammation and reduced skin thickness in Balb/c mice. Our findings support nanocapsules as an effective drug delivery system to enhance αBIS stability, bioavailability, and therapeutic efficacy in AD treatment.

Antileishmanial effect of podophyllotoxin and podophyllin on Leishmania major in vitro and in vivo.

Therapeutic research is very important in the prevention and treatment of leishmaniasis due to problems such as drug resistance, scarring and disease recurrence. The aim of this study was to determine how Leishmania major responds to the anti-leishmaniasis properties of podophyllotoxin and podophyllin. Cultured Leishmania promastigotes were exposed to different concentrations of podophyllotoxin and podophyllin for 24 and 48 h. Then, during the animal phase, Balb/c mice were experimentally injected with Leishmania promastigotes. After wounding, the effects of 0.5% podophyllotoxin and 25% podophyllin on reducing wound diameter and the number of amastigotes in the wound were evaluated. Podophyllotoxin and podophyllin were 83% and 59% lethal to Leishmania major promastigotes at the highest concentrations (200 µg/ml) and time (48 h). In the in vivo study, the mean lesion diameter at the end of treatment in the negative control group was 15.10 mm compared to 14.21 mm and 11.55 mm in the 25% podophyllin and 0.5% podophyllotoxin groups, respectively. Although both agents reduced the size of mice wounds and the number of amastigotes in the wounds, podophyllotoxin was more effective in this regard. Based on the results, podophyllotoxin and podophyllin can be used as leishmaniasis drugs after further research.

Comparison of the immune response and protection against the experimental Toxoplasma gondii infection elicited by immunization with the recombinant proteins BAG1, ROP8, and BAG1-ROP8.

Toxoplasmosis is one of the most dangerous zoonotic diseases, causing serious economic losses worldwide due to abortion and reproductive problems. Vaccination is the best way to prevent disease; thus, it is imperative to develop a candidate vaccine for toxoplasmosis. BAG1 and ROP8 have the potential to become vaccine candidates. In this study, rTgBAG1, rTgROP8, and rTgBAG1-rTgROP8 were used to evaluate the immune effect of vaccines in each group by detecting the humoral and cellular immune response levels of BABL/c mice after immunization and the ability to resist acute and chronic infection with Toxoplasma gondii (T. gondii). We divided the mice into vaccine groups with different proteins, and the mice were immunized on days 0, 14, and 28. The protective effects of different proteins against T. gondii were analysed by measuring the cytokines, serum antibodies, splenocyte proliferation assay results, survival time, and number and diameter of brain cysts of mice after infection. The vaccine groups exhibited substantially higher IgG, IgG1, and IgG2a levels and effectively stimulated lymphocyte proliferation. The levels of IFN-γ and IL-2 in the vaccine group were significantly increased. The survival time of the mice in each vaccine group was prolonged and the diameter of the cysts in the vaccine group was smaller; rTgBAG1-rTgROP8 had a better protection. Our study showed that the rTgBAG1, rTgROP8, and rTgBAG1-rTgROP8 recombinant protein vaccines are partial but effective approaches against acute or chronic T. gondii infection. They are potential candidates for a toxoplasmosis vaccine.

External Volume Expansion: Timing and Effects on the Rate of Fat Graft Retention in BALB/c Nude Mice.

BACKGROUND/AIM: Fat grafting has been widely used for soft-tissue augmentation. External volume expansion (EVE) is a favorable tool for improvement in the rate of fat graft retention. However, few studies have focused on the most appropriate time for its implementation. In this study, BALB/c nude mice were used to investigate the effective time for the implementation of external volume expansion to improve the rate of fat retention. MATERIALS AND METHODS: Sixteen mice were divided into four groups, and EVE was performed at different time points before or both before and after fat grafting. Fat tissue from a human donor was injected into the mice following EVE. Visual assessment, micro-computed tomography analysis, and histopathological evaluation were used to assess fat retention. RESULTS: After 10 weeks, the group that underwent EVE 5 days before fat grafting demonstrated a significantly higher preserved fat volume, as determined by micro-computed tomography (p<0.05). Moreover, the group that received additional EVE after fat grafting exhibited a higher retention rate compared to the groups receiving EVE only before grafting (p<0.05). Histopathological analysis indicated that swelling, edema, and inflammation were more pronounced in the group with EVE immediately before grafting, while angiogenesis and lipogenesis were more active in the group with additional EVE after grafting. CONCLUSION: EVE is a safe and effective approach for improving the rate of fat graft retentions. Furthermore, the timing of external tissue expansion plays a crucial role in fat retention. Based on our animal study, performing EVE immediately before and after fat grafting may be an effective strategy for enhancing the rate of fat graft retentions.

Contribution of parasite and host genotype to immunopathology of schistosome infections.

Background: The role of pathogen genotype in determining disease severity and immunopathology has been studied intensively in microbial pathogens including bacteria, fungi, protozoa, and viruses, but is poorly understood in parasitic helminths. The medically important blood fluke Schistosoma mansoni is an excellent model system to study the impact of helminth genetic variation on immunopathology. Our laboratory has demonstrated that laboratory schistosome populations differ in sporocyst growth and cercarial production in the intermediate snail host and worm establishment and fecundity in the vertebrate host. Here, we (i) investigate the hypothesis that schistosome genotype plays a significant role in immunopathology and related parasite life history traits in the vertebrate mouse host and (ii) quantify the relative impact of parasite and host genetics on infection outcomes. Methods: We infected BALB/c and C57BL/6 mice with four different laboratory schistosome populations from Africa and the Americas. We quantified disease progression in the vertebrate host by measuring body weight and complete blood count (CBC) with differential over an infection period of 12 weeks. On sacrifice, we assessed parasitological (egg and worm counts, fecundity), immunopathological (organ measurements and histopathology), and immunological (CBC with differential and cytokine profiles) characteristics to determine the impact of parasite and host genetics. Results: We found significant variation between parasite populations in worm numbers, fecundity, liver and intestine egg counts, liver and spleen weight, and fibrotic area, but not in granuloma size. Variation in organ weight was explained by egg burden and by intrinsic parasite factors independent of egg burden. We found significant variation between infected mouse lines in cytokines (IFN-γ, TNF-α), eosinophil, lymphocyte, and monocyte counts. Conclusions: This study showed that both parasite and host genotype impact the outcome of infection. While host genotype explains most of the variation in immunological traits, parasite genotype explains most of the variation in parasitological traits, and both host and parasite genotype impact immunopathology outcomes.

Brilaroxazine lipogel displays antipsoriatic activity in imiquimod-induced mouse model.

BACKGROUND: Dopamine (D) and serotonin (5-HT) pathways contribute to psoriasis pathobiology. Disruptions incite increased inflammatory mediators, keratinocyte activation and deterioration, and worsening symptoms. Brilaroxazine (RP5063), which displays potent high binding affinity to D2/3/4 and 5-HT1A/2A/2B/7 receptors and a moderate affinity to serotonin transporter (SERT), may affect the underlying psoriasis pathology. METHODS: An imiquimod-induced psoriatic mouse model (BALB/c) evaluated brilaroxazine's activity in a topical liposomal-aqueous gel (Lipogel) formulation. Two of the three groups (n = 6 per) underwent induction with 5% imiquimod, and one group received topical brilaroxazine Lipogel (Days 1-11). Assessments included (1) Psoriasis Area and Severity Index (PASI) scores (Days 1-12), skin histology for Baker score based on H&E stained tissue (Day 12), and serum blood collection for serum cytokine analysis (Day 12). One-way ANOVA followed by post hoc Dunnett's t-test evaluated significance (p < 0.05). RESULTS: Imiquimod-induced animal Baker scores were higher versus Sham non-induced control's results (p < 0.001). Brilaroxazine Lipogel had significantly (p = 0.003) lower Baker scores versus the induced Psoriasis group. Brilaroxazine PASI scores were lower (p = 0.03) versus the induced Psoriasis group (Days 3-12), with the greatest effect in the last 3 days. The induced Psoriasis group showed higher Ki-67 and TGF-ß levels versus non-induced Sham controls (p = 0.001). The brilaroxazine Lipogel group displayed lower levels of these cytokines versus the induced Psoriasis group, Ki-67 (p = 0.001) and TGF-ß (p = 0.008), and no difference in TNF-α levels versus Sham non-induced controls. CONCLUSION: Brilaroxazine Lipogel displayed significant activity in imiquimod-induced psoriatic animals, offering a novel therapeutic strategy.

Layering vaccination with antibiotic therapy results in protection and clearance of Burkholderia pseudomallei in Balb/c mice.

Melioidosis is a disease that is difficult to treat due to the causative organism, Burkholderia pseudomallei being inherently antibiotic resistant and it having the ability to invade, survive, and replicate in an intracellular environment. Combination therapy approaches are routinely being evaluated in animal models with the aim of improving the level of protection and clearance of colonizing bacteria detected. In this study, a subunit vaccine layered with the antibiotic finafloxacin was evaluated in vivo against an inhalational infection with B. pseudomallei in Balb/c mice. Groups of mice vaccinated, infected, and euthanized at antibiotic initiation had a reduced bacterial load compared to those that had not been immunized. In addition, the subunit vaccine provided a synergistic effect when it was delivered with a CpG ODN and finafloxacin was initiated at 48 h post-challenge. Vaccination was also shown to improve the outcome, in a composite measure of survival and clearance. In summary, layering a subunit vaccine with the antibiotic finafloxacin is a promising therapeutic alternative for use in the treatment of B. pseudomallei infections.

Sudapyridine (WX-081) antibacterial activity against Mycobacterium avium, Mycobacterium abscessus, and Mycobacterium chelonae in vitro and in vivo.

Sudapyridine (WX-081) is a structural analog of bedaquiline (BDQ), which shows anti-tuberculosis and non-tuberculous mycobacteria (NTM) activities but, unlike BDQ, did not prolong QT interval in animal model studies. This study evaluated the antibacterial activity of this novel compound against Mycobacterium avium, Mycobacterium abscessus, and Mycobacterium chelonae in vitro and in vivo. The minimum inhibitory concentration (MIC) of WX-081 against three kinds of non-tuberculous mycobacteria (NTM) clinical strains was determined using microplate-based alamarBlue assay (MABA), and the antibacterial activity of WX-081 against NTM in J774A.1 cells and mice was evaluated. MIC ranges of WX-081 against clinical strains of M. avium and M. abscessus were 0.05-0.94 µg/mL, 0.88-7.22 µg/mL (M. abscessus subsp. abscessus), and 0.22-8.67 µg/mL (M. abscessus subsp. massiliense), respectively, which were slightly higher than those of BDQ. For M. avium, M. abscessus, and M. chelonae, WX-081 can reduce the intracellular bacterial load by 0.13-1.18, 0.18-1.50, and 0.17-1.03 log10 colony forming units (CFU)/mL, respectively, in a concentration-dependent manner. WX-081 has bactericidal activity against three NTM species in mice. WX-081 exhibited anti-NTM activity to the same extent as BDQ both in vivo and in vitro. WX-081 is a promising clinical candidate and should be studied further in clinical trials. IMPORTANCE: Due to the rapidly increased cases globally, non-tuberculous mycobacteria (NTM) disease has become a significant public health problem. NTM accounted for 11.57% of all mycobacterial isolates in China, with a high detection rate of Mycobacterium abscessus, Mycobacterium avium, and Mycobacterium chelonae during 2000-2019. Treatment of NTM infection is often challenging, as natural resistance to most antibiotics is quite common among different NTM species. Hence, identifying highly active anti-NTM agents is a priority for potent regimen establishment. The pursuit of new drugs to treat multidrug-resistant tuberculosis may also identify some agents with strong activity against NTM. Sudapyridine (WX-081) is a structural analog of bedaquiline (BDQ), which was developed to retain the anti-tuberculosis efficacy but eliminates the severe side effects of BDQ. This study initially evaluated the antimicrobial activity of this novel compound against M. avium, M. abscessus, and M. chelonae in vitro, in macrophages and mice, respectively.

Contribution of parasite and host genotype to immunopathology of schistosome infections.

Background: The role of pathogen genotype in determining disease severity and immunopathology has been studied intensively in microbial pathogens including bacteria, fungi, protozoa, and viruses, but is poorly understood in parasitic helminths. The medically important blood fluke Schistosoma mansoni is an excellent model system to study the impact of helminth genetic variation on immunopathology. Our laboratory has demonstrated that laboratory schistosome populations differ in sporocyst growth and cercarial production in the intermediate snail host and worm establishment and fecundity in the vertebrate host. Here, we (i) investigate the hypothesis that schistosome genotype plays a significant role in immunopathology and related parasite life history traits in the vertebrate mouse host and (ii) quantify the relative impact of parasite and host genetics on infection outcomes. Methods: We infected BALB/c and C57BL/6 mice with four different laboratory schistosome populations from Africa and the Americas. We quantified disease progression in the vertebrate host by measuring body weight and complete blood count (CBC) with differential over an infection period of 12 weeks. On sacrifice, we assessed parasitological (egg and worm counts, fecundity), immunopathological (organ measurements and histopathology), and immunological (CBC with differential and cytokine profiles) characteristics to determine the impact of parasite and host genetics. Results: We found significant variation between parasite populations in worm numbers, fecundity, liver and intestine egg counts, liver and spleen weight, and fibrotic area, but not in granuloma size. Variation in organ weight was explained by egg burden and by intrinsic parasite factors independent of egg burden. We found significant variation between infected mouse lines in cytokines (IFN-γ, TNF-α), eosinophil, lymphocyte, and monocyte counts. Conclusions: This study showed that both parasite and host genotype impact the outcome of infection. While host genotype explains most of the variation in immunological traits, parasite genotype explains most of the variation in parasitological traits, and both host and parasite genotype impact immunopathology outcomes.

In vitro and in vivo activity of a novel oxamide-hydrazone hybrid derivative against triple-negative breast cancer.

Triple-negative breast cancer is a subtype of breast cancer with poor clinical outcome, and currently, no effective targeted therapies are available. Since cancer develops owing to deregulation of apoptosis, employing therapeutic strategies with the ability to target the molecules involved in apoptosis induction would provide a valid approach to hinder tumor progression. Hydrazide-hydrazones and oxamide molecules are the subject of intense studies due to their anticancer effects via apoptosis induction. In the present study, we attempted to elucidate the mechanism of action of a synthesized compound (compound A) in inducing cell death. Annexin/PI and Western blotting analyses, DAPI staining, mitochondrial membrane potential probe, and flow cytometry were applied for the in vitro evaluations. 4T1 syngeneic mouse model and immunohistochemistry were used for the in vivo assessments. Compound A caused cell death by inducing apoptosis in MDA-MB-231 cells in a mitochondrial-dependent manner at high concentrations after 72 h of incubation. Compound A also impeded tumor growth in a 4T1 syngeneic mouse model as evidenced by hematoxylin and eosin staining of the tumors. Furthermore, it significantly diminished the expression of pro-caspase-3, Ki67, and CD31 markers in the tumor sections. Conclusively, this study for the first time reports the anti-cancer efficacy of compound A in both in vitro and in vivo models and its potential in the treatment of triple-negative breast cancer.

Can Ganciclovir and Quercetin-P188 Ameliorate Cytomegalovirus Induced Hearing Loss?

OBJECTIVE: Determine whether combination therapy with ganciclovir (GCV) and a Quercetin-P188 solution improves hearing outcomes in a murine cytomegalovirus (CMV) model. METHODS: BALB/c mice were infected with murine CMV on postnatal day 3 (p3). Quercetin was solubilized in saline using P188 (QP188). Treatment groups received either GCV, QP188, GCV and QP188, or P188 delivery vehicle BID at 12-hour intervals via intraperitoneal injection. All treatment groups were treated for 14 days starting at p3. Uninfected controls were treated with the combined regimen, saline or P188 delivery vehicle. Auditory thresholds were assessed using distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) testing at 4, 6, and 8 weeks of age. Temporal bones from separate CMV-infected groups were harvested at p10, and viral load was determined by quantitative polymerase chain reaction. RESULTS: CMV-infected mice receiving combination therapy GCV+QP188 demonstrated statistically significant lower ABR (p < 0.001) and DPOAE thresholds (p < 0.001) compared with mice treated with GCV monotherapy, QP188 monotherapy, and P188 delivery vehicle at 4, 6, and 8 weeks of age. GCV+QP188 combination therapy, GCV monotherapy, and QP188 monotherapy resulted in a nonsignificant reduction in mean viral titers compared to P188 monotherapy (p = 0.08). CONCLUSION: Combining GCV with the excipients quercetin and P188 effectively ameliorated CMV-induced sensorineural hearing loss in a murine model. This result may be partially explained by a reduction in viral titers in mouse temporal bones that correlate with in vitro studies demonstrating additive antiviral effect in cell culture. LEVEL OF EVIDENCE: NA Laryngoscope, 134:1457-1463, 2024.