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ABSTRACT: Endoscopic thyroidectomy is a minimally invasive surgical approach that has become popular due to its cosmetic advantages and reduced post-operative discomfort. Central to the success of this procedure is the accurate identification of the midline, which becomes a challenge in endoscopic surgeries. We propose a novel method of using methylene blue, a Food and Drug Administration-approved dye, which offers the ability to clearly mark the midline, enhancing orientation and reducing the potential for injury to critical anatomical structures. Although using methylene blue has many benefits, there are drawbacks, including the requirement for intraoperative ultrasonography. Continued research and clinical experience will be critical in improving and extending its use in the field of thyroid surgery.
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The synthesis of a novel carboxylate-type organic linker-based luminescent MOF (Zn(H2L) (L1)) (named PUC2) (H2L = 2-aminoterephtalic acid, L1 = 1-(3-aminopropyl) imidazole) is reported by the solvothermal method and comprehensively characterized using single-crystal XRD, PXRD, FTIR, TGA, XPS, FESEM, HRTEM, and BET. PUC2 selectively reacts with nitric oxide (âªNO) with a detection limit of 0.08 µM, and a quenching constant (0.5 × 104 M-1) indicating a strong interaction with âªNO. PUC2 sensitivity remains unaffected by cellular proteins or biologically relevant metals (Cu2+/ Fe3+/Mg2+/ Na+/K+/Zn2+), RNS/ROS, or H2S to score âªNO in living cells. Lastly, we used PUC2 to demonstrate that H2S inhibition increases âªNO production by ~ 14-30% in various living cells while exogenous H2S suppresses âªNO production, indicating that the modulation of cellular âªNO production by H2S is rather generic and not restricted to a particular cell type. In conclusion, PUC2 can successfully detect âªNO production in living cells and environmental samples with considerable potential for its application in improving the understanding of the role of âªNO in biological samples and study the inter-relationship between âªNO and H2S.
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Sulfuro de Hidrógeno , Óxido NítricoRESUMEN
Surgical emergencies are common in the critical care setting and require prompt diagnosis and management. Here, we discuss some of the surgical emergencies involving the gastrointestinal, hepatobiliary, and genitourinary sites. In addition, foreign body aspiration and necrotizing soft-tissue infections have been elaborated. Clinicians should be aware of the risk factors, keys examination findings, diagnostic modalities, and medical as well as surgical treatment options for these potentially fatal illnesses.
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Urgencias Médicas , Unidades de Cuidados Intensivos , Humanos , Factores de RiesgoRESUMEN
Despite the increasing number of women within medical professions, gender equality in career advancement and leadership positions still remains a challenge due to numerous barriers including unbalanced domestic responsibilities, discrimination, and rigidity in career structures. Here, we discuss ways to achieve work-life balance and family planning as well as some of the challenges women face in medicine and nursing careers and outline strategies for individuals and organizations to overcome them.
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Movilidad Laboral , Liderazgo , Humanos , FemeninoRESUMEN
Skeletal muscle atrophy/wasting is associated with impaired protein metabolism in diverse physiological and pathophysiological conditions. Elevated levels of reactive oxygen species (ROS), disturbed redox status, and weakened antioxidant defense system are the major contributing factors toward atrophy. Regulation of protein metabolism by controlling ROS levels and its associated catabolic pathways may help in treating atrophy and related clinical conditions. Although cinnamaldehyde (CNA) enjoys the established status of antioxidant and its role in ROS management is reported, impact of CNA on skeletal muscle atrophy and related pathways is still unexplored. In the current study, the impact of CNA on C2C12 myotubes and the possible protection of cultured cells from H 2 O 2 -induced atrophy is examined. Myotubes were treated with H 2 O 2 in the presence and absence of CNA and the changes in the antioxidative, proteolytic systems, and mitochondrial functions were scored. Morphological analysis showed significant protective effects of CNA on length, diameter, and nuclei fusion index of myotubes. The evaluation of biochemical markers of atrophy; creatine kinase, lactate dehydrogenase, succinate dehydrogenase along with the study of muscle-specific structural protein (i.e., myosin heavy chain-fast [MHCf] type) showed significant protection of proteins by CNA. CNA pretreatment not only checked the activation of proteolytic systems (ubiquitin-proteasome E3-ligases [MuRF1/Atrogin1]), autophagy [Beclin1/LC3B], cathepsin L, calpain, caspase), but also prevented any alteration in the activities of antioxidative defense enzymes (catalase, glutathione- S-transferase, glutathione-peroxidase, superoxide dismutase, glutathione reductase). The results suggest that CNA protects myotubes from H 2 O 2 -induced atrophy by inhibiting/resisting the amendments in proteolytic systems and maintains cellular redox-balance.
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Acroleína/análogos & derivados , Antioxidantes/farmacología , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Acroleína/farmacología , Animales , Línea Celular , Peróxido de Hidrógeno/toxicidad , Ratones , Músculo Esquelético/patología , Atrofia Muscular/patología , Proteolisis/efectos de los fármacosRESUMEN
Clofazimine and high-dose rifapentine have each separately been associated with treatment-shortening activity when incorporated into tuberculosis (TB) treatment regimens. We hypothesized that both modifications, i.e., the addition of clofazimine and the replacement of rifampin with high-dose rifapentine, in the first-line regimen for drug-susceptible TB would significantly shorten the duration of treatment necessary for cure. We tested this hypothesis in a well-established BALB/c mouse model of TB chemotherapy and also in a C3HeB/FeJ mouse model in which mice can develop caseous necrotic lesions, an environment where rifapentine and clofazimine may individually be less effective. In both mouse models, replacing rifampin with high-dose rifapentine and adding clofazimine in the first-line regimen resulted in greater bactericidal and sterilizing activity than either modification alone, suggesting that a rifapentine- and clofazimine-containing regimen may have the potential to significantly shorten the treatment duration for drug-susceptible TB. These data provide preclinical evidence supporting the evaluation of regimens combining high-dose rifapentine and clofazimine in clinical trials.
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Antituberculosos/administración & dosificación , Clofazimina/administración & dosificación , Rifampin/análogos & derivados , Tuberculosis/tratamiento farmacológico , Animales , Antibióticos Antituberculosos/administración & dosificación , Modelos Animales de Enfermedad , Esquema de Medicación , Quimioterapia Combinada/métodos , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Rifampin/administración & dosificaciónRESUMEN
The potent antituberculosis activity and long half-life of bedaquiline make it an attractive candidate for use in long-acting/extended-release formulations for the treatment of latent tuberculosis infection (LTBI). Our objective was to evaluate a long-acting injectable (LAI) bedaquiline formulation in a validated paucibacillary mouse model of LTBI. Following immunization with Mycobacterium bovis rBCG30, BALB/c mice were challenged by aerosol infection with M. tuberculosis H37Rv. Treatment began 13 weeks after challenge infection with one of the following regimens: an untreated negative-control regimen; positive-control regimens of daily rifampin (10 mg/kg of body weight), once-weekly rifapentine (15 mg/kg) and isoniazid (50 mg/kg), or daily bedaquiline (25 mg/kg); test regimens of one, two, or three monthly doses of LAI bedaquiline at 160 mg/dose (BLAI-160); and test regimens of daily bedaquiline at 2.67 mg/kg (B2.67), 5.33 mg/kg (B5.33), or 8 mg/kg (B8) to deliver the same total amount of bedaquiline as one, two, or three doses of BLAI-160, respectively. All drugs were administered orally, except for BLAI-160 (intramuscular injection). The primary outcome was the decline in M. tuberculosis lung CFU counts during 12 weeks of treatment. The negative- and positive-control regimens performed as expected. One, two, and three doses of BLAI-160 resulted in decreases of 2.9, 3.2, and 3.5 log10 CFU/lung, respectively, by week 12. Daily oral dosing with B2.67, B5.33, and B8 decreased lung CFU counts by 1.6, 2.8, and 4.1 log10, respectively. One dose of BLAI-160 exhibited activity for at least 12 weeks. The sustained activity of BLAI-160 indicates that it shows promise as a short-course LTBI treatment requiring few patient encounters to ensure treatment completion.
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Antituberculosos/farmacología , Diarilquinolinas/farmacología , Tuberculosis Latente/tratamiento farmacológico , Administración Oral , Animales , Antituberculosos/administración & dosificación , Antituberculosos/farmacocinética , Diarilquinolinas/administración & dosificación , Diarilquinolinas/farmacocinética , Modelos Animales de Enfermedad , Femenino , Inyecciones Intramusculares , Masculino , Ratones , Ratones Endogámicos BALB C , Pruebas de Sensibilidad Microbiana , Mycobacterium tuberculosis/efectos de los fármacosRESUMEN
[This corrects the article DOI: 10.1371/journal.ppat.1006389.].
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Signals modulating the production of Mycobacterium tuberculosis (Mtb) virulence factors essential for establishing long-term persistent infection are unknown. The WhiB3 redox regulator is known to regulate the production of Mtb virulence factors, however the mechanisms of this modulation are unknown. To advance our understanding of the mechanisms involved in WhiB3 regulation, we performed Mtb in vitro, intraphagosomal and infected host expression analyses. Our Mtb expression analyses in conjunction with extracellular flux analyses demonstrated that WhiB3 maintains bioenergetic homeostasis in response to available carbon sources found in vivo to establish Mtb infection. Our infected host expression analysis indicated that WhiB3 is involved in regulation of the host cell cycle. Detailed cell-cycle analysis revealed that Mtb infection inhibited the macrophage G1/S transition, and polyketides under WhiB3 control arrested the macrophages in the G0-G1 phase. Notably, infection with the Mtb whiB3 mutant or polyketide mutants had little effect on the macrophage cell cycle and emulated the uninfected cells. This suggests that polyketides regulated by Mtb WhiB3 are responsible for the cell cycle arrest observed in macrophages infected with the wild type Mtb. Thus, our findings demonstrate that Mtb WhiB3 maintains bioenergetic homeostasis to produce polyketide and lipid cyclomodulins that target the host cell cycle. This is a new mechanism whereby Mtb modulates the immune system by altering the host cell cycle to promote long-term persistence. This new knowledge could serve as the foundation for new host-directed therapeutic discovery efforts that target the host cell cycle.
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Mycobacterium tuberculosis/fisiología , Tuberculosis/fisiopatología , Animales , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Femenino , Puntos de Control de la Fase G1 del Ciclo Celular , Interacciones Huésped-Patógeno , Humanos , Macrófagos/metabolismo , Macrófagos/microbiología , Ratones Endogámicos BALB C , Mycobacterium tuberculosis/genética , Puntos de Control de la Fase S del Ciclo Celular , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Tuberculosis/metabolismo , Tuberculosis/microbiologíaRESUMEN
The antileprosy drug clofazimine was recently repurposed as part of a newly endorsed short-course regimen for multidrug-resistant tuberculosis. It also enables significant treatment shortening when added to the first-line regimen for drug-susceptible tuberculosis in a mouse model. However, clofazimine causes dose- and duration-dependent skin discoloration in patients, and the optimal clofazimine dosing strategy in the context of the first-line regimen is unknown. We utilized a well-established mouse model to systematically address the impacts of duration, dose, and companion drugs on the treatment-shortening activity of clofazimine in the first-line regimen. In all studies, the primary outcome was relapse-free cure (culture-negative lungs) 6 months after stopping treatment, and the secondary outcome was bactericidal activity, i.e., the decline in the lung bacterial burden during treatment. Our findings indicate that clofazimine activity is most potent when coadministered with first-line drugs continuously throughout treatment and that equivalent treatment-shortening results are obtained with half the dose commonly used in mice. However, our studies also suggest that clofazimine at low exposures may have negative impacts on treatment outcomes, an effect that was evident only after the first 3 months of treatment. These data provide a sound evidence base to inform clofazimine dosing strategies to optimize the antituberculosis effect while minimizing skin discoloration. The results also underscore the importance of conducting long-term studies to allow the full evaluation of drugs administered in combination over long durations.
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Antituberculosos/uso terapéutico , Clofazimina/uso terapéutico , Tuberculosis/tratamiento farmacológico , Animales , Modelos Animales de Enfermedad , Femenino , Ratones , Ratones Endogámicos BALB C , Distribución Aleatoria , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológicoRESUMEN
BACKGROUND: Elevated levels of inflammatory molecules are key players in muscle wasting/atrophy leading to human morbidity. TNFα is a well-known pro-inflammatory cytokine implicated in the pathogenesis of muscle wasting under diverse clinical settings. S-allyl cysteine (SAC), an active component of garlic (Allium sativum), has established anti-oxidant and anti-inflammatory effects in various cell types. However, the impact of SAC on skeletal muscle pathology remains unexplored. Owing to the known anti-inflammatory properties of SAC, we investigated whether pre-treatment with SAC has a protective role in TNFα-induced atrophy in cultured myotubes. METHODS AND RESULTS: C2C12 myotubes were treated with TNFα (100ng/ml) in the presence or absence of SAC (0.01mM). TNFα treatment induced atrophy in myotubes by up-regulating various proteolytic systems i.e. cathepsin L, calpain, ubiquitin-proteasome E3-ligases (MuRF1/atrogin1), caspase 3 and autophagy (Beclin1/LC3B). TNFα also induced the activation of NFκB by stimulating the degradation of IκBα (inhibitor of NFκB), in myotubes. The alterations in proteolytic systems likely contribute to the degradation of muscle-specific proteins and reduce the myotube length, diameter and fusion index. The SAC supplementation significantly impedes TNFα-induced protein loss and protects myotube morphology by suppressing protein catabolic systems and endogenous level of inflammatory molecules namely TNFα, IL-6, IL-1ß, TNF-like weak inducer of apoptosis (TWEAK), fibroblast growth factor-inducible 14 (Fn14) and Nox. CONCLUSION AND GENERAL SIGNIFICANCE: Our findings reveal anti-atrophic role for SAC, as it prevents alterations in protein metabolism and protects myotubes by regulating the level of inflammatory molecules and multiple proteolytic systems responsible for muscle atrophy.
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Cisteína/análogos & derivados , Mediadores de Inflamación/metabolismo , Músculo Esquelético/efectos de los fármacos , Atrofia Muscular/prevención & control , Factor de Necrosis Tumoral alfa/farmacología , Animales , Autofagia/efectos de los fármacos , Autofagia/genética , Línea Celular , Cisteína/farmacología , Citocinas/genética , Citocinas/metabolismo , Expresión Génica/efectos de los fármacos , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patología , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Atrofia Muscular/metabolismo , Proteolisis/efectos de los fármacos , Receptor de TWEAK/genética , Receptor de TWEAK/metabolismo , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
Mycobacterium tuberculosis (Mtb) is a facultative intracellular pathogen and the second largest contributor to global mortality caused by an infectious agent after HIV. In infected host cells, Mtb is faced with a harsh intracellular environment including hypoxia and the release of nitric oxide (NO) and carbon monoxide (CO) by immune cells. Hypoxia, NO and CO induce a state of in vitro dormancy where Mtb senses these gases via the DosS and DosT heme sensor kinase proteins, which in turn induce a set of â¼47 genes, known as the Mtb Dos dormancy regulon. On the contrary, both iNOS and HO-1, which produce NO and CO, respectively, have been shown to be important against mycobacterial disease progression. In this review, we discuss the impact of O2, NO and CO on Mtb physiology and in host responses to Mtb infection as well as the potential role of another major endogenous gas, hydrogen sulfide (H2S), in Mtb pathogenesis.
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Gasotransmisores/fisiología , Mycobacterium tuberculosis/fisiología , Tuberculosis Pulmonar/metabolismo , Monóxido de Carbono/fisiología , Humanos , Sulfuro de Hidrógeno/metabolismo , Mycobacterium tuberculosis/genética , Óxido Nítrico/fisiología , Oxígeno/fisiología , Especies Reactivas de Oxígeno/metabolismo , Tuberculosis Pulmonar/microbiologíaRESUMEN
Understanding the evolutionary and genomic mechanisms responsible for turning the soil-derived saprophytic mycobacteria into lethal intracellular pathogens is a critical step towards the development of strategies for the control of mycobacterial diseases. In this context, Mycobacterium indicus pranii (MIP) is of specific interest because of its unique immunological and evolutionary significance. Evolutionarily, it is the progenitor of opportunistic pathogens belonging to M. avium complex and is endowed with features that place it between saprophytic and pathogenic species. Herein, we have sequenced the complete MIP genome to understand its unique life style, basis of immunomodulation and habitat diversification in mycobacteria. As a case of massive gene acquisitions, 50.5% of MIP open reading frames (ORFs) are laterally acquired. We show, for the first time for Mycobacterium, that MIP genome has mosaic architecture. These gene acquisitions have led to the enrichment of selected gene families critical to MIP physiology. Comparative genomic analysis indicates a higher antigenic potential of MIP imparting it a unique ability for immunomodulation. Besides, it also suggests an important role of genomic fluidity in habitat diversification within mycobacteria and provides a unique view of evolutionary divergence and putative bottlenecks that might have eventually led to intracellular survival and pathogenic attributes in mycobacteria.
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Evolución Molecular , Transferencia de Gen Horizontal , Genes Bacterianos , Mycobacterium/genética , Proteínas Bacterianas/clasificación , Proteínas Bacterianas/genética , Especiación Genética , Genoma Bacteriano , Hemeritrina/genética , Secuencias Repetitivas Esparcidas , Proteínas de Transporte de Membrana/genética , Familia de Multigenes , Mycobacterium/inmunología , Mycobacterium/metabolismo , Plásmidos/genética , Proteoma/genética , Selección GenéticaRESUMEN
Large ventral hernias require complex surgical techniques, such as component separation. We are presenting a case of an incisional hernia measuring 15×8 cm. The hernia was covered with an overlying thin layer of skin and hernia sac. The skin of this layer was densely adherent to the underlying hernial sac. Because of the thin hernial sac and adherent nature of the skin, approximately 3 cm of the hernial sac was preserved. We used this hernial sac as the anterior sheath 'extension' for a tension-free closure. Posterior component separation with transverse abdominis muscle release was done to close the posterior layer without tension and to place a 23×16 cm mesh in the retrorectus plane. By using the hernial sac in repair, we avoided anterior component separation and achieved tension-free closure of the anterior layer.
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Hernia Ventral , Herniorrafia , Hernia Incisional , Mallas Quirúrgicas , Humanos , Hernia Ventral/cirugía , Hernia Incisional/cirugía , Hernia Incisional/prevención & control , Herniorrafia/métodos , Femenino , Masculino , Persona de Mediana EdadRESUMEN
The incidence of adrenal cysts is 0.06% and only 9% of these are true mesothelial cysts. Here, we present a case of a true mesothelial cyst together with a review of the literature. A female in her 30s presented to the surgical outpatient department complaining of right flank pain. Her contrast-enhanced CT scan revealed a 7.5×6.5×4.5 cm right adrenal gland cyst. The patient underwent a laparoscopic right adrenalectomy. Immunohistopathology revealed the cyst to be mesothelial in nature. The majority of true mesothelial adrenal cysts are benign, unilateral and more common in women. Any adrenal cyst diagnosed as a functional lesion or one that may be malignant or with a diameter of 5 cm or greater requires surgical care whereas smaller lesions can be managed conservatively. Laparoscopic adrenalectomy for an adrenal cyst of diameter greater than 6 cm is a safe and feasible procedure in expert hands if there is no invasion of surrounding tissue.
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Enfermedades de las Glándulas Suprarrenales , Neoplasias de las Glándulas Suprarrenales , Quistes , Laparoscopía , Humanos , Femenino , Enfermedades de las Glándulas Suprarrenales/diagnóstico por imagen , Enfermedades de las Glándulas Suprarrenales/cirugía , Glándulas Suprarrenales/diagnóstico por imagen , Glándulas Suprarrenales/cirugía , Glándulas Suprarrenales/patología , Quistes/diagnóstico por imagen , Quistes/cirugía , Neoplasias de las Glándulas Suprarrenales/cirugía , Adrenalectomía/métodosRESUMEN
Corona mortis (CM) is an anastomotic vessel between the inferior epigastric or external iliac vessels and the obturator or internal iliac vessels. The Latin meaning of it is 'crown of death' which corresponds to massive haemorrhage caused by injury to this vessel during surgery. The incidence of this vessel is around 50% in the hemipelvis. We are presenting an intraoperative video of a right laparoscopic totally extraperitoneal mesh hernioplasty demonstrating a CM artery in the right hemipelvis. Care was taken to prevent injury to this vessel. CO2 insufflation pressure was reduced to less than 10 mm Hg to see any venous variant of this vessel. Carefully, polypropylene mesh was placed without a fixation device. Anatomical knowledge of the CM vessel is therefore essential in preventing injury for surgeons who approach the inguinal and retropubic regions.
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Hernia Inguinal , Laparoscopía , Humanos , Arteria Ilíaca/cirugía , Herniorrafia , Mallas Quirúrgicas/efectos adversos , Arterias/cirugía , Hernia Inguinal/cirugíaRESUMEN
BACKGROUND: Direct specimen sequencing (DSS) offers the promise of enhanced pathogen detection and disease diagnosis. METHODS: A single healthcare network, retrospective chart review over a 3-year period was completed for all cases in which DSS was submitted, in addition to conventional testing (CT) for workup of an infectious disease. We sought to compare results (concordance and discordance) from these 2 techniques in order to evaluate any additional yield from DSS over CT. Additionally, we calculated mean turnaround time (TAT) and average cost for obtaining DSS on all specimens. RESULTS: A total of 23 patients' specimens were sent for DSS. DSS and CT concordance occurred in 91% (21/23) of cases. DSS testing was able to identify specific pathogens in 17.4% (4/23) of patients, out of which 4% (1/23) were discordant. The respective mean TAT and total cost per specimen for DSS were 6 days and $821.52 (range $573-$1590), respectively. CONCLUSIONS: In our limited cohort of patients, there was significant concordance between the 2 testing modalities primarily due to negative tests. DSS did not provide significant additional yield in the infectious diagnosis in our cohort compared to CT. Short TAT may provide advantage in the detection of fastidious organisms, but high cost remains a limitation. Larger sample size may reveal a clinically meaningful difference.
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Derivación y Consulta , Humanos , Estudios RetrospectivosRESUMEN
Purpose: These days laparoscopic inguinal hernia surgery, both totally extraperitoneal (TEP) and transabdominal preperitoneal (TAPP), is a commonly performed procedure due to advancements in laparoscopic instruments and the availability of skilled laparoscopic surgeons. The purpose of this study was to compare the perioperative complications of these two procedures. Methods: This was a prospective observational study between July 2019 and December 2020. Perioperative complications were compared with a 6-month follow-up. It included 144 patients, of whom 71 underwent TAPP repair and 73 underwent TEP repair. The selection was based on the surgeon's choice. Results: Early postoperative complications were scrotal edema (12 cases in TEP and 16 in TAPP), urinary retention (one case in TEP), ecchymosis (six cases in TEP and two in TAPP), and scrotal subcutaneous emphysema (two cases in TEP). On follow-up, seroma was found in a total of 22 cases, of which 12 were TEP and 10 were TAPP. While only one case of TAPP developed surgical site infection. There was no statistically significant difference in hospital stay between the two groups (p = 0.58). The pain scores significantly decreased throughout recovery and were comparable between the groups. Neither group experienced a recurrence during the 6-month follow-up. Fifty-eight patients developed Clavien-Dindo grade I complications, one had grade II, and three had grade IIIa complications. Conclusion: With the increasing experience of the surgical fraternity in laparoscopic surgery, TEP and TAPP were proven to be comparable in terms of duration of surgery, postoperative complications, hospital stay, pain scores, and recurrence during the 6-month follow-up.
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Non-tuberculous mycobacterial (NTM) infections occur in both immunocompromised and immunocompetent hosts and are an increasingly recognized cause of morbidity and mortality. The hallmark of pulmonary mycobacterial infections is the formation of granuloma in the lung. Our study focuses on the role of heme oxygenase-1 (HO-1), a cytoprotective enzyme, in the regulation of granuloma development and maturation following infection with Mycobacterium avium. We examined the role of HO-1 in regulating monocyte chemoattractant protein-1 (MCP-1) and chemokine receptor 2 (CCR2), two molecules involved in monocyte-macrophage cell trafficking after infection. We showed that RAW 264.7 mouse monocytes exposed to M. avium expressed HO-1 and MCP-1. Inhibition of HO by zinc protoporphyrin-IX led to inhibition of MCP-1 and increased expression of CCR2, its cognate receptor. HO-1â»/â» mice did not develop organized granuloma in their lungs, had higher lung colony forming unit of M. avium when infected with intratracheal M. avium, and had loose collections of inflammatory cells in the lung parenchyma. Mycobacteria were found only inside defined granulomas but not outside granuloma in the lungs of HO-1âº/⺠mice. In HO-1â»/â» mice, mycobacteria were also found in the liver and spleen and showed increased mortality. Peripheral blood monocytes isolated from GFP⺠mice and given intravenously to HO-1âº/⺠mice localized into tight granulomas, while in HO-1â»/â» mice they remained diffusely scattered in areas of parenchymal inflammation. Higher MCP-1 levels were found in bronchoalveolar lavage fluid of M. avium infected HO-1(-/-) mice and CCR2 expression was higher in HO-1â»/â» alveolar macrophages when compared with HO-1âº/⺠mice. CCR2 expression localized to granuloma in HO-1âº/⺠mice but not in the HO-1â»/â» mice. These findings strongly suggest that HO-1 plays a protective role in the control of M. avium infection.
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Quimiocina CCL2/metabolismo , Granuloma/enzimología , Hemo-Oxigenasa 1/metabolismo , Proteínas de la Membrana/metabolismo , Receptores CCR2/metabolismo , Tuberculosis Pulmonar/enzimología , Animales , Línea Celular , Recuento de Colonia Microbiana , Granuloma/microbiología , Pulmón/patología , Ratones , Ratones Noqueados , Mycobacterium avium , Protoporfirinas , ARN Mensajero/metabolismo , Tuberculosis Pulmonar/microbiología , Tuberculosis Pulmonar/patologíaRESUMEN
BACKGROUND: A high-fat diet (HFD) induced perturbation of gut microbiota is a major contributory factor to promote the pathophysiology of HFD-associated metabolic syndrome. The HFD could also increase the susceptibility to the microbial infections warranting the use of antibiotics which are independently capable of impacting both gut microbiota and metabolic syndrome. Further, the usage of antibiotics in individuals consuming HFD can impact mitochondrial function that can be associated with an elevated risk of chronic conditions like inflammatory bowel disease (IBD). Despite this high propensity to infections in individuals on HFD, the link between duration of HFD and antibiotic treatment, and its impact on diversity of the gut microbiome and features of metabolic syndrome is not well established. In this study, we have addressed these knowledge gaps by examining how the gut microbiota profile changes in HFD-fed mice receiving antibiotic intervention in the form of amoxicillin. We also determine whether antibiotic treatment in HFD-fed mice may adversely impact the ability of immune cells to clear microbial infections. METHODS AND RESULTS: We have subjected mice to HFD and chow diet (CD) for 3 weeks, and a subset of these mice on both diets received antibiotic intervention in the form of amoxicillin in the 3rd week. Body weight and food intake were recorded for 3 weeks. After 21 days, all animals were weighted and sacrificed. Subsequently, these animals were evaluated for basic haemato-biochemical and histopathological attributes. We used 16S rRNA sequencing followed by bioinformatics analysis to determine changes in gut microbiota in these mice. We observed that a HFD, even for a short-duration, could successfully induce the partial pathophysiology typical of a metabolic syndrome, and substantially modulated the gut microbiota in mice. The short course of amoxicillin treatment to HFD-fed mice resulted in beneficial effects by significantly reducing fasting blood glucose and skewing the number of thrombocytes towards a normal range. Remarkably, we observed a significant remodelling of gut microbiota in amoxicillin-treated HFD-fed mice. Importantly, some gut microbes associated with improved insulin sensitivity and recovery from metabolic syndrome only appeared in amoxicillin-treated HFD-fed mice reinforcing the beneficial effects of antibiotic treatment in the HFD-associated metabolic syndrome. Moreover, we also observed the presence of gut-microbiota unique to amoxicillin-treated HFD-fed mice that are also known to improve the pathophysiology associated with metabolic syndrome. However, both CD-fed as well as HFD-fed mice receiving antibiotics showed an increase in intestinal pathogens as is typically observed for antibiotic treatment. Importantly though, infection studies with S. aureus and A. baumannii, revealed that macrophages isolated from amoxicillin-treated HFD-fed mice are comparable to those isolated from mice receiving only HFD or CD in terms of susceptibility, and progression of microbial infection. This finding clearly indicated that amoxicillin treatment does not introduce any additional deficits in the ability of macrophages to combat microbial infections. CONCLUSIONS: Our results showed that amoxicillin treatment in HFD-fed mice exert a beneficial influence on the pathophysiological attributes of metabolic syndrome which correlates with a significant remodelling of gut microbiota. A novel observation was the increase in microbes known to improve insulin sensitivity following amoxicillin treatment during short-term intake of HFD. Even though there is a minor increase in gut-resistant intestinal pathogens in amoxicillin-treated groups, there is no adverse impact on macrophages with respect to their susceptibility and ability to control infections. Taken together, this study provides a proof of principle for the exploration of amoxicillin treatment as a potential therapy in the people affected with metabolic syndrome.