Evaluation of Berberine as an Adjunct to TB Treatment.

Tuberculosis (TB) is the global health problem with the second highest number of deaths from a communicable disease after COVID-19. Although TB is curable, poor health infrastructure, long and grueling TB treatments have led to the spread of TB pandemic with alarmingly increasing multidrug-resistant (MDR)-TB prevalence. Alternative host modulating therapies can be employed to improve TB drug efficacies or dampen the exaggerated inflammatory responses to improve lung function. Here, we investigated the adjunct therapy of natural immune-modulatory compound berberine in C57BL/6 mouse model of pulmonary TB. Berberine treatment did not affect Mtb growth in axenic cultures; however, it showed increased bacterial killing in primary murine bone marrow-derived macrophages and human monocyte-derived macrophages. Ad libitum berberine administration was beneficial to the host in combination with rifampicin and isoniazid. Berberine adjunctive treatment resulted in decreased lung pathology with no additive or synergistic effects on bacterial burdens in mice. Lung immune cell flow cytometry analysis showed that adjunctive berberine treatment decreased neutrophil, CD11b+ dendritic cell and recruited interstitial macrophage numbers. Late onset of adjunctive berberine treatment resulted in a similar phenotype with consistently reduced numbers of neutrophils both in lungs and the spleen. Together, our results suggest that berberine can be supplemented as an immunomodulatory agent depending on the disease stage and inflammatory status of the host.

Early immune response in large yellow croaker (Larimichthys crocea) after immunization with oral vaccine.

Mesoporous silica nanoparticles (MSNs) have been used in the field of biomedicine as antigen carriers and adjuvants for protective antigens. In the present study, an oral nanovaccine against Vibrio alginolyticus was prepared employing MSNs as carriers. The uptake of the dihydrolipoamide dehydrogenase (DLDH) antigens in the intestine of large yellow croaker was evaluated using an immunohistochemistry assay. Additionally, the effects of the nanovaccine on the early immune response in large yellow croaker were investigated via oral vaccination. The presence of the antigens was detected in the mucosa and lamina propria of the foregut, midgut, and hindgut of large yellow croaker at 3 h following oral immunization. The expression levels of cytokines (i.e., lysozyme, IFN-γ, IFITM, TNF-α, IL-1ß, IL-2, IL-4, IL-10, and IL-13) in the intestine, spleen, and head kidney tissues of large yellow croaker before and after the immune challenge were determined via RT-qPCR assay. The obtained results revealed that the expression levels of lysozyme, IFN-γ, IFITM, TNF-α, IL-1ß, IL-2, IL-4, IL-10, and IL-13 in the intestine and head kidney of the vaccinated large yellow croaker, as well as the expression of lysozyme, IL-1ß, and IL-10 in the spleen, exhibited time-dependent oscillation regulation patterns. Notably, the nanovaccine immunization could induce early (6 h) and high expression of IFN-γ in the spleen and kidney tissues after the bacterial infection. The current study supplements the available data on the early immune response to fish nanovaccines. It also provides a valuable theoretical basis for the future development of large yellow croaker oral vaccines.

Subpopulations of Stressed Yersinia pseudotuberculosis Preferentially Survive Doxycycline Treatment within Host Tissues.

Severe systemic bacterial infections result in colonization of deep tissues, which can be very difficult to eliminate with antibiotics. It remains unclear if this is because antibiotics are not reaching inhibitory concentrations within tissues, if subsets of bacteria are less susceptible to antibiotics, or if both contribute to limited treatment efficacy. To detect exposure to doxycycline (Dox) present in deep tissues following treatment, we generated a fluorescent transcriptional reporter derived from the tet operon to specifically detect intracellular tetracycline exposure at the single bacterial cell level. Dox exposure was detected in the spleen 2 h after intraperitoneal injection, and by 4 h postinjection, this treatment resulted in a significant decrease in viable Yersinia pseudotuberculosis bacteria in the spleen. Nitric oxide-stressed bacteria preferentially survived treatment, suggesting that stress was sufficient to alter Dox susceptibility. Many bacteria (∼10%) survived a single dose of Dox, and the antibiotic accumulated at the periphery of microcolonies to growth inhibitory concentrations until 48 h posttreatment. After this time point, antibiotic concentrations decreased and bacterial growth resumed. Dox-treated mice eventually succumbed to the infection, albeit with significantly prolonged survival relative to that of untreated mice. These results indicate that Dox delivery by intraperitoneal injection results in rapid diffusion of inhibitory concentrations of antibiotic into the spleen, but stressed cells preferentially survive drug treatment, and bacterial growth resumes once drug concentrations decrease. This fluorescent reporter strategy for antibiotic detection could easily be modified to detect the concentration of additional antimicrobial compounds within host tissues following drug administration.IMPORTANCE Bacterial infections are very difficult to treat when bacteria spread into the bloodstream and begin to replicate within deep tissues, such as the spleen. Subsets of bacteria can survive antibiotic treatment, but it remains unclear if this survival is because of limited drug diffusion into tissues, or if there are changes within the bacteria, promoting survival of some bacterial cells. Here, we have developed a fluorescent reporter to detect doxycycline (Dox) diffusion into host tissues, and we show that Dox impacts the bacterial population within hours of administration and inhibits bacterial growth for 48 h. However, bacterial growth resumes when antibiotic concentrations decrease. Subsets of bacteria, stressed by the host response to infection, survive Dox treatment at a higher rate. These results provide critical information about the dynamics that occur within deep tissues following antibiotic administration and suggest that subsets of bacteria are predisposed to survive inhibitory concentrations of antibiotic before exposure.

Immunomodulatory activity and protective effects of chokeberry fruit extract on Listeria monocytogenes infection in mice.

Chokeberry (Aronia melanocarpa) fruit extracts (CE) are rich in polyphenols and usually exhibit immunomodulatory, anti-viral and anti-bacterial effects. We have previously shown that the CE used in this study activated macrophages and stimulated effector T cell differentiation in vitro. When applied orally to healthy mice, CE increased the proportion of CD11c+ dendritic cells in the gut-associated lymphoid tissue. CE-pretreated BALB/c mice readily eradicated orally ingested Listeria monocytogenes as evidenced by a slighter decrease in body weight and number of bacteria recovered from the spleen and reduced spleen size compared to the control infected mice. CE pretreatment in infected mice resulted in higher proportions of CD11b+ macrophages and CD8+ cytotoxic T cells both in the gut and the spleen. Phagocytosis, reactive oxygen species production and the proportions of activated CD86+ macrophages (CD11b+) and dendritic cells (CD11c+) were also enhanced in CE-pretreated infected mice. Furthermore, the expression of inducible nitric oxide synthase and IL-6 was increased in CE-pretreated infected mice and similar results were obtained in peritoneal macrophages in vitro. This effect of CE was associated with increased phosphorylation of IκB and Notch1 production. Finally, CE pretreatment elevated the proportion of perforin-producing cells in the spleen compared to control infected mice. This study demonstrates that prophylactic treatment with CE leads to more rapid eradication of bacterial infection with L. monocytogenes predominantly through increased activity of myeloid cells in the gut and in the spleen.

High dose of dietary vitamin D3 modulated the yellow catfish (Pelteobagrus fulvidraco) splenic innate immune response after Edwardsiella ictaluri infection.

Vitamin D3 (VD3) has been shown to modulate the innate immune response in mammals but this has been rarely reported in fish. The current study found that increasing dietary VD3 content can reduce the density of yellow to dark brown pigmented macrophage aggregates (PMAs) in the spleens of yellow catfish infected with Edwardsiella ictaluri. The results of next-generation sequencing showed that a high dose of dietary VD3 (16,600 IU/kg) mainly affected the splenic immune response during Edwardsiella ictaluri infection via negative regulation of 'NF-κΒ transcription factor activity', 'NIK/NF-κΒ signaling' and the 'i-kappab kinase/NF-κΒ signaling' pathways. Follow-up qPCR showed that dietary VD3 increased the expression of NF-κΒ inhibitor iκb-α, decreased the expression of nf-κb p65, il-6, il1-ß and tnf-α, and down-regulated the expression of nik, ikks and nf-κb p52 in the NIK/NF-kappaB signaling pathway. The above results indicate that dietary VD3 can modulate the splenic innate immune response of yellow catfish after Edwardsiella ictaluri infection by inhibiting the NF-κB activation signaling pathways.

Betulin efficiently suppresses the process of an experimental Listeria monocytogenes infection as an antagonist against listeriolysin O.

Listeria monocytogenes (Lm) is a widespread foodborne intracellular pathogen that invades a variety of cells, causing abortions and severe human diseases. After internalization into host cells, pore-forming cytolysin listeriolysin O (LLO) disrupts the phagosome, which allows the bacterium to survive and colonize the cytoplasm, providing the bacterium the chance to infect neighboring cells. Betulin is an extracted natural compound from birch bark with diverse pharmacological activities. Here, we showed that LLO-induced rabbit red blood cell lysis in vitro was inhibited by preincubation with betulin, which suppressed the oligomerization process. Infectious assays performed with human monocyte macrophages indicated that betulin significantly protected cells against Lm-induced cell injury. In addition, Balb/c mice were used to perform a general infection, and betulin administration obviously inhibited organ damage and bacterial burden in livers and spleens of infected mice. In conclusion, betulin obviously inhibited Lm-induced cell injury in vitro and protected against infection in vivo through an antivirulence effect. Our results showed betulin as a new candidate against listeriosis by targeting LLO and highlight the potential of natural product-based medicine to be applied in the treatment of pathogenic infections.

Immunization With Mycobacterium tuberculosis Antigens Encapsulated in Phosphatidylserine Liposomes Improves Protection Afforded by BCG.

Liposomes have been long considered as a vaccine delivery system but this technology remains to be fully utilized. Here, we describe a novel liposome-based subunit vaccine formulation for tuberculosis (TB) based on phosphatidylserine encapsulating two prominent TB antigens, Ag85B, and ESAT-6. We show that the resulting liposomes (Lipo-AE) are stable upon storage and can be readily taken up by antigen presenting cells and that their antigenic cargo is delivered and processed within endosomal cell compartments. The Lipo-AE vaccine formulation combined with the PolyIC adjuvant induced a mixed Th1/Th17-Th2 immune response to Ag85B but only a weak response to ESAT-6. An immunization regimen based on systemic delivery followed by mucosal boost with Lipo-AE resulted in the accumulation of resident memory T cells in the lungs. Most importantly though, when Lipo-AE vaccine candidate was administered to BCG-immunized mice subsequently challenged with low dose aerosol Mycobacterium tuberculosis, we observed a significant reduction of the bacterial load in the lungs and spleen compared to BCG alone. We therefore conclude that the immunization with mycobacterial antigens delivered by phosphatidylserine based liposomes in combination with Poly:IC adjuvant may represent a novel BCG boosting vaccination strategy.

The Application of a Nanomaterial Optical Fiber Biosensor Assay for Identification of Brucella Nomenspecies.

Bacteria in the genus Brucella are the cause of brucellosis in humans and many domestic and wild animals. A rapid and culture-free detection assay to detect Brucella in clinical samples would be highly valuable. Nanomaterial optical fiber biosensors (NOFS) are capable of recognizing DNA hybridization events or other analyte interactions with high specificity and sensitivity. Therefore, a NOFS assay was developed to detect Brucella DNA from cultures and in tissue samples from infected mice. An ionic self-assembled multilayer (ISAM) film was coupled to a long-period grating optical fiber, and a nucleotide probe complementary to the Brucella IS711 region and modified with biotin was bound to the ISAM by covalent conjugation. When the ISAM/probe duplex was exposed to lysate containing ≥100 killed cells of Brucella, or liver or spleen tissue extracts from Brucella-infected mice, substantial attenuation of light transmission occurred, whereas exposure of the complexed fiber to non-Brucella gram-negative bacteria or control tissue samples resulted in negligible attenuation of light transmission. Oligonucleotide probes specific for B. abortus, B. melitensis, and B. suis could also be used to detect and differentiate these three nomenspecies. In summary, the NOFS biosensor assay detected three nomenspecies of Brucella without the use of polymerase chain reaction within 30 min and could specifically detect low numbers of this bacterium in clinical samples.

Sodium butyrate ameliorates Corynebacterium pseudotuberculosis infection in RAW264.7 macrophages and C57BL/6 mice.

Corynebacterium pseudotuberculosis (CP) infection in livestock has become highly difficult to control. To decrease the incidence of CP infection, the supplementation of feed with non-antibiotic antibacterial substances is a potential approach. The aim of this study was to assess the effects of sodium butyrate (NaB), a potential alternative to antibiotics, on CP infection in RAW264.7 macrophages and C57BL/6 mice. Our data showed that NaB (2 mM) significantly ameliorated CPinfection in RAW264.7 macrophages and decreased the bacterial load in the spleens of infected mice. By real-time PCR, we found that NaB induced significant decreases in zinc-dependent superoxide dismutase (sodC) and tip protein C (spaC) expression in CP from infected-RAW264.7 cells and in phospholipase D (pld) and spaC expression in CP from the spleens of infected mice. NaB treatment significantly up-regulated cathelicidin-related antimicrobial peptide (cramp) expression in spleens of mice infected with CP. Furthermore, NaB alleviated histopathological changes in spleens of CP-infected mice. In conclusion, NaB ameliorated CP infection in RAW264.7 macrophages and C57BL/6 mice, and these effects may be related to the modulation of sodC, spaC, pld, and cramp expression.

Erythromycin and florfenicol treatment of rainbow trout Oncorhynchus mykiss (Walbaum) experimentally infected with Flavobacterium psychrophilum.

Flavobacterium psychrophilum is responsible for significant economic losses in rainbow trout aquaculture. Antimicrobial treatment remains the primary means of control; however, there are limited choices available for use. The objectives of the study were therefore to determine the minimum inhibitory concentrations for erythromycin and florfenicol in selected F. psychrophilum isolates and to evaluate their clinical treatment efficacy in experimentally infected rainbow trout. All isolates tested had moderate susceptibility to florfenicol and erythromycin except one isolate, which had low susceptibility to erythromycin. Two isolates (one with moderate and one with low susceptibility to erythromycin) were used in an experimental infection trial. Rainbow trout juveniles were injected intraperitoneally with 108 cfu/fish and after mortality had begun, fish were given erythromycin- and florfenicol-medicated feed at a rate of 75 mg kg- 1 day- 1 and 10 mg kg- 1  day- 1 fish body weight, respectively, for 10 consecutive days. The splenic F. psychrophilum load was determined using an rpoC quantitative PCR throughout the 30-day trial. Relative to antibiotic-free controls, erythromycin treatment significantly (p < 0.05) reduced mortality of rainbow trout juveniles infected with FPG101, even when treatment was initiated after clinical signs developed.

Prophylactic Palmitoylethanolamide Prolongs Survival and Decreases Detrimental Inflammation in Aged Mice With Bacterial Meningitis.

Easy-to-achieve interventions to promote healthy longevity are desired to diminish the incidence and severity of infections, as well as associated disability upon recovery. The dietary supplement palmitoylethanolamide (PEA) exerts anti-inflammatory and neuroprotective properties. Here, we investigated the effect of prophylactic PEA on the early immune response, clinical course, and survival of old mice after intracerebral E. coli K1 infection. Nineteen-month-old wild type mice were treated intraperitoneally with two doses of either 0.1 mg PEA/kg in 250 µl vehicle solution (n = 19) or with 250 µl vehicle solution only as controls (n = 19), 12 h and 30 min prior to intracerebral E. coli K1 infection. The intraperitoneal route was chosen to reduce distress in mice and to ensure exact dosing. Survival time, bacterial loads in cerebellum, blood, spleen, liver, and microglia counts and activation scores in the brain were evaluated. We measured the levels of IL-1ß, IL-6, MIP-1α, and CXCL1 in cerebellum and spleen, as well as of bioactive lipids in serum in PEA- and vehicle-treated animals 24 h after infection. In the absence of antibiotic therapy, the median survival time of PEA-pre-treated infected mice was prolonged by 18 h compared to mice of the vehicle-pre-treated infected group (P = 0.031). PEA prophylaxis delayed the onset of clinical symptoms (P = 0.037). This protective effect was associated with lower bacterial loads in the spleen, liver, and blood compared to those of vehicle-injected animals (P ≤ 0.037). PEA-pre-treated animals showed diminished levels of pro-inflammatory cytokines and chemokines in spleen 24 h after infection, as well as reduced serum concentrations of arachidonic acid and of one of its metabolites, 20-hydroxyeicosatetraenoic acid. In the brain, prophylactic PEA tended to reduce bacterial titers and attenuated microglial activation in aged infected animals (P = 0.042). Our findings suggest that prophylactic PEA can counteract infection associated detrimental responses in old animals. Accordingly, PEA treatment slowed the onset of infection symptoms and prolonged the survival of old infected mice. In a clinical setting, prophylactic administration of PEA might extend the potential therapeutic window where antibiotic therapy can be initiated to rescue elderly patients.

Evaluation of intrinsic and acquired immune cells infiltration in kidney and spleen of the mice infected with systemic candidiasis and treated with chloroform fraction of Zataria Multiflora Boiss.

BACKGROUND AND AIMS: Despite the use of antifungal drugs, the visceral candidiasis is associated with a high mortality rate. The aims of this study were an evaluation of intrinsic and acquired immune cells infiltration in kidney and spleen of the mice infected with systemic candidiasis and treated with chloroform fraction of Zataria Multiflora Boiss. MATERIALS AND METHODS: Candida albicans (C. albicans) ATCC10231 clinical standard strain was isolated. C. albicans LD50 was determined. The laboratory animal (BALB/C mouse) infection with the visceral candidiasis was performed. The kidney and spleen tissues were stained with PAS and prepared for confirmation under the microscope. The Zataria Multiflora Boiss (Shiraz thyme) was prepared and the effects on the infected group were assessed. The kidney and spleen mononuclear cells (MNCs) were prepared and the flow cytometry technique was performed for the assessment of Th1, Th17, and Treg cells. RESULTS: The LD50 and LD totals were 1.5 × 108 and 2 × 108 Yeast/0.1 ml, respectively. In mice which had a drug intervention, including chloroform fraction of Zataria Multiflora Boiss, thymol, carvacrol or fluconazole, fungal purification was greater in the spleen than in the kidney. Among those mice without medication intervention, fungal clearance was higher in the kidney. The highest percentage of TH1 cells was in group 1 and then group 4 and in groups 2 and 3 respectively. Moreover, there was a significant difference between groups 4 and 5 and also 6 and 7. The percentage of TH1 cells in the spleen MNCs was higher than that of the kidney cells, which is the difference between the groups except for group 7. The percentage of TH17 cells in the kidney and spleen of all drug-receiving groups exhibited a significant increase compared to groups 6 and 7. The percentage of Treg cells in the kidney and the spleen only in the extract-receiving group had a significant decrease compared to the non-drug receiving group and the other groups receiving group depicted no significant difference in the percentage of Treg cells. CONCLUSION: In addition to the direct effect on the fungus proven in vitro, the extract exhibits immunosuppressive effects, and thus can degrade the fungus through this way. The results demonstrated that the fraction of Zataria Multiflora Boiss can be considered as a powerful alternative to C. albicans therapy along with other therapies.

Azole-resistant and -susceptible Aspergillus fumigatus isolates show comparable fitness and azole treatment outcome in immunocompetent mice.

No data are available on the in vivo impact of infections with in vitro azole-resistant Aspergillus fumigatus in immunocompetent hosts. Here, the aim was to investigate fungal fitness and treatment response in immunocompetent mice infected with A. fumigatus (parental strain [ps]) and isogenic mutants carrying either the mutation M220K or G54W (cyp51A). The efficacy of itraconazole (ITC) and posaconazole (PSC) was investigated in mice, intravenously challenged either with a single or a combination of ps and mutants (6 × 105 conidia/mouse). Organ fungal burden and clinical parameters were measured. In coinfection models, no fitness advantage was observed for the ps strain when compared to the mutants (M220K and G54W) independent of the presence or absence of azole-treatment. For G54W, M220K, and the ps, no statistically significant difference in ITC and PSC treatment was observed in respect to fungal kidney burden. However, clinical parameters suggest that in particular the azole-resistant strain carrying the mutation G54W caused a more severe disease than the ps strain. Mice infected with G54W showed a significant decline in body weight and lymphocyte counts, while spleen/body weight ratio and granulocyte counts were increased. In immunocompetent mice, in vitro azole-resistance did not translate into therapeutic failure by either ITC or PSC; the immune system appears to play the key role in clearing the infection.

Optimization and characterization of a murine lung infection model for the evaluation of novel therapeutics against Burkholderia cenocepacia.

Several B. cenocepacia mouse models are available to study the pulmonary infection by this Burkholderia cepacia complex (BCC) species. However, a characterized B. cenocepacia mouse model to evaluate the efficacy of potential new antibacterial therapies is not yet described. Therefore, we optimized and validated the course of infection (i.e. bacterial proliferation in lung, liver and spleen) and the efficacy of a reference antibiotic, tobramycin (TOB), in a mouse lung infection model. Furthermore, the local immune response and histological changes in lung tissue were studied during infection and treatment. A reproducible lung infection was observed when immunosuppressed BALB/c mice were infected with B. cenocepacia LMG 16656. Approximately 50 to 60% of mice infected with this BCC species demonstrated a dissemination to liver and spleen. TOB treatment resulted in a two log reduction in lung burden, prevented dissemination of B. cenocepacia to liver and spleen and significantly reduced levels of proinflammatory cytokines. As this mouse model is characterized by a reproducible course of infection and efficacy of TOB, it can be used as a tool for the in vivo evaluation of new antibacterial therapies.

Effect of dietary bacteriophage supplementation on internal organs, fecal excretion, and ileal immune response in laying hens challenged by Salmonella Enteritidis.

With the current researches on replacing antibiotics with different dietary interventions, bacteriophages (BP) are potential antimicrobial intervention because of their ability to affect specific bacteria. A study was conducted to evaluate the role of BP against Salmonella enterica serovar Enteritidis (SE) on SE internal organs colonization and ileum immune response in laying hens. Hens were challenged both orally and intracloacally with 108 cfu/mL cells of nalidixic acid resistant Salmonella Enteritidis (SENAR). Thirty-two Single Comb White Leghorns were randomly allocated to 4 dietary treatments: 1) unchallenged control (negative control; T1), 2) SENAR challenged control (positive control; T2), 3) SENAR challenged + 0.1% BP (T3), and 4) SENAR challenged + 0.2% BP (T4). The number of SENAR in the ceca was significantly reduced by 0.2% BP supplementation (P < 0.05) at 7 d post infection (dpi). The respective number of SENAR was reduced from 2.9 log cfu/gm in T2 and T3 to 2.0 log cfu/gm in T4. There was no significant effect of T3 on reduction of numbers of cecal SENAR. A significant reduction of SENAR was observed in the liver with gall bladder (LGB) from 0.75 in T2 to 0.18 log cfu/gm in T4. In the spleen, T4 significantly reduced (P < 0.05) SENAR to 0.56 log cfu/gm compared to T2 and T3 (0.94 log cfu/gm). There was no significant effect of T3 in reduction of prevalence of spleen SENAR. By supplementing 0.2% BP (T4), the SENAR in the ovary was reduced to 0 log cfu/gm. There was a significant reduction (P < 0.05) in fecal SENAR at 6 dpi by T4 (0.71 log cfu/gm) compared to the positive control (1.57 log cfu/gm). The expression of interferon (IFN)-Γ, interleukin (IL)-6, and IL-10 was significantly increased in the ileum by SENAR challenge compared to the negative control. This study suggests that apart from commonly used prebiotics or probiotics, BP are pathogen-specific and can be used as one of the dietary strategies to reduce SE colonization and induce immune modulation in laying hens.

Protective efficacy of a lipid antigen vaccine in a guinea pig model of tuberculosis.

The bacillus Calmette Guérin (BCG) vaccine, the only licensed vaccine against TB, displays partial and variable efficacy, thus making the exploitation of novel vaccination strategies a major priority. Most of the current vaccines in pre-clinical or clinical development are based on the induction of T cells recognizing protein antigens. However, a large number of T cells specific for mycobacterial lipids are induced during infection, suggesting that lipid-based vaccines might represent an important component of novel sub-unit vaccines. Here, we investigated whether immunization with defined mycobacterial lipid antigens induces protection in guinea pigs challenged with M. tuberculosis. Two purified mycobacterial lipid antigens, the diacylated sulfoglycolipids (Ac2SGL) and the phosphatidyl-myo-inositol dimannosides (PIM2) were formulated in biophysically characterized liposomes made of dimethyl-dioctadecyl-ammonium (DDA) and synthetic trehalose 6,6'-dibehenate (TDB). In three protection trials, a reduction of bacterial load in the spleen of inoculated animals was consistently observed compared to the unvaccinated group. Moreover, a reduction in the number of lesions and severity of pathology was detected in the lungs and spleen of the lipid vaccine group compared to unvaccinated controls. As the degree of protection achieved is similar to that observed using protein antigens in the same guinea pig model, these promising results pave the way to future investigations of lipid antigens as subunit vaccines.

Therapeutic effects of traditional Chinese medicine Niubeixiaohe in mouse tuberculosis models.

ETHNOPHARMACOLOGICAL RELEVANCE: The traditional Chinese medicine Niubeixiaohe (NBXH) is an effective anti-tuberculosis prescription, which is made up of Bulbus Fritillariae Cirrhosae, Rhizoma Bletillae, Radix Platycodonis, Fructus Arctii, Herba Houttuyniae and Glutinous rice. In this study, NBXH powder (I) and three kinds of NBXH extracts (II, III, and IV) were prepared. The water decoction of NBXH had been used to treat TB in clinic sixteen years suggested that it was effective to treat TB. AIM OF THE STUDY: This study evaluated the effects of different processing products of NBXH on mouse TB model in vivo and provide a new Chinese medicine for the clinical treatment of TB. MATERIALS AND METHODS: In this study, 120 female BALB/c mice infected with Mycobacterium tuberculosis H37Rv, were treated with distilled water, M. vaccae vaccine, the low, middle and high doses of NBXH I, the low, middle and high doses of NBXH II, the low, middle and high doses of NBXH III, the low, middle and high doses of NBXH IV for 12 weeks, respectively. RESULTS: The body weights of mice in all NBXH groups were higher than that in the water group. The weight indexes of the spleens in M. vaccae group, the middle dose of NBXH II group, the low dose of NBXH IV group and in the high dose of NBXH IV group were significantly lower than that in the water group(P<0.05). Compared with the water group, the spleen colony counts in the low dose of NBXH I group, the high dose of NBXH II group, the low dose of NBXH III group and the high dose of NBXH IV group reduced by 0.43, 0.46, 0.73, 0.58 logs (P<0.05), respectively. But the lung colony counts had no significant difference between each group. Pulmonary general pathology and histopathology displayed that the lung lesions in treatment groups were improved at certain degree, especially in the low dose of NBXH IIIand IV groups, in which their areas of the lesions were less than 50%, and the half normal lung structure in half of the mice could be observed. CONCLUSION: Powder and three extracts of traditional Chinese medicine NBXH all had anti-tuberculosis therapeutic effects on mouse tuberculosis model, and this study provided a base for the further development of Chinese patent medicine NBXH. Also, this is the first report on comprehensive experimental research of NBXH extracts coming from six kinds of traditional Chinese medicine.

Combined antifungal therapy against systemic murine infections by rare Cryptococcus species.

Cryptococcus albidus and Cryptococcus laurentii are uncommon species of this genus that in recent decades have increasingly caused opportunistic infections in humans, mainly in immunocompromised patients; the best therapy for such infection being unknown. Using a murine model of systemic infection by these fungi, we have evaluated the efficacy of amphotericin B (AMB) at 0.8 mg/kg, administered intravenously, fluconazole (FLC) or voriconazole (VRC), both administered orally, at 25 mg/kg and the combination of AMB plus VRC against three C. albidus and two C. laurentii strains. All the treatments significantly reduced the fungal burden in all the organs studied. The combination showed a synergistic effect in the reduction in fungal load, working better than both monotherapies. The histopathological study confirmed the efficacy of the treatments.

Formulation studies of InhA inhibitors and combination therapy to improve efficacy against Mycobacterium tuberculosis.

Previously, structure-based drug design was used to develop substituted diphenyl ethers with potency against the Mycobacterium tuberculosis (Mtb) enoyl-ACP reductase (InhA), however, the highly lipophilic centroid compound, SB-PT004, lacked sufficient efficacy in the acute murine Mtb infection model. A next generation series of compounds were designed with improved specificity, potency against InhA, and reduced cytotoxicity in vitro, but these compounds also had limited solubility. Accordingly, solubility and pharmacokinetics studies were performed to develop formulations for this class and other experimental drug candidates with high logP values often encountered in drug discovery. Lead diphenyl ethers were formulated in co-solvent and Self-Dispersing Lipid Formulations (SDLFs) and evaluated in a rapid murine Mtb infection model that assesses dissemination to and bacterial burden in the spleen. In vitro synergy studies were performed with the lead diphenyl ether compounds, SB-PT070 and SB-PT091, and rifampin (RIF), which demonstrated an additive effect, and that guided the in vivo studies. Combinatorial therapy in vivo studies with these compounds delivered in our Self-Micro Emulsifying Drug Delivery System (SMEDDS) resulted in an additional 1.4 log10 CFU reduction in the spleen of animals co-treated with SB-PT091 and RIF and an additional 1.7 log10 reduction in the spleen with animals treated with both SB-PT070 and RIF.

Evaluation of in vivo antimycobacterial activity of some folklore medicinal plants and enumeration of colony forming unit in murine model.

OBJECTIVES: The present study was carried out to investigate the in vivo antimycobacterial activity of methanol extract of Alstonia scholaris and Mucuna imbricata in murine model. MATERIALS AND METHODS: Female BALB/c mice were infected with the Mycobacterium tuberculosis H37Rv suspension. Extracts were administered orally for 2 weeks from 7th day postinfection at a dose of 200 mg/kg and rifampicin at 20 mg/kg as standard. The synergistic groups were 10 and 100 mg/kg for rifampicin and extract, respectively. RESULTS: The final body weight of mycobacteria-infected group was significantly reduced (15.41 ± 0.42, P < 0.01), but following treatment with the plant extract plus rifampicin could elevate the body weight. Colony forming unit (CFU) count of lung (8.71 ± 0.01) and spleen (8.59 ± 0.01) was significantly higher in infected and untreated group (P < 0.01). It was observed that activity of the synergistic group displayed powerful and maximum response against tuberculosis (TB) infection with lower CFU counts. Histopathology study showed cells such as lymphocytes, epithelioid, Langhans giant cell, and fibrous tissue proliferation in lungs; depletion of lymphocytes in the spleen. CONCLUSIONS: The data indicate that methanol extract of A. scholaris has potential antimycobacterial activity, and the synergistic group consisting of rifampicin and A. scholaris could be a rational choice for the treatment of TB.