Quality of life from childhood to adulthood: Perspectives from adult patients with pediatric-onset intestinal failure.

Adult patients with pediatric onset short bowel syndrome (SBS) or intestinal failure (IF) have been described as a distinct population warranting further research. The aim of this exploratory study aimed was to offer initial insights into this population's navigation of childhood, adolescence, and transition into adulthood. Both quantitative and qualitative data were collected from a convenience sample of adults with pediatric-onset SBS/IF using a disease-specific pilot survey; 14 questionnaires were completed. Responses indicated childhood and adulthood were complex and marked by joys and trials, while adolescence was experienced by many as a particularly challenging time. As adults, numerous patients experienced barriers to accessing the medical care they desired and described difficulties finding experienced and knowledgeable providers who listened and offered individualized care. This study highlights the importance of further studying this unique patient population, suggesting it can offer critical insights to inform the development of interventions and transition programs.

Prognostic factors of brain metastasis and survival among HER2-positive metastatic breast cancer patients: a systematic literature review.

BACKGROUND: Patients with breast cancer who overexpress the human epidermal growth factor receptor 2 (HER2) and subsequently develop brain metastasis (BM) typically experience poor quality of life and low survival. We conducted a comprehensive literature review to identify prognostic factors for BM and predictors of survival after developing BM, and the effects of therapies with different mechanisms of action among patients with HER2+ breast cancer (BC). METHODS: A prespecified search strategy was used to identify research studies investigating BM in patients with HER2+ BC published in English during January 1, 2009-to June 25, 2021. Articles were screened using a two-phase process, and data from selected articles were extracted. RESULTS: We identified 25 published articles including 4097 patients with HER2+ BC and BM. Prognostic factors associated with shorter time to BM diagnosis after initial BC diagnosis included younger age, hormone receptor negative status, larger tumor size or higher tumor grade, and lack of treatment with anti-HER2 therapy. Factors predictive of longer survival after BM included having fewer brain lesions (< 3 or a single lesion) and receipt of any treatment after BM, including radiosurgery, neurosurgery and/or systemic therapy. Patients receiving combination trastuzumab and lapatinib therapy or trastuzumab and pertuzumab therapy had the longest median survival compared with other therapies assessed in this review. CONCLUSIONS: More research is needed to better understand risk factors for BM and survival after BM in the context of HER2+ BC, as well as the assessment of new anti-HER2 therapy regimens that may provide additional therapeutic options for BM in these patients.

Incidence of pneumonitis/interstitial lung disease induced by HER2-targeting therapy for HER2-positive metastatic breast cancer.

PURPOSE: Anti-human epidermal growth factor receptor 2 (HER2) therapies are associated with interstitial lung disease (ILD), also referred to as pneumonitis. In this literature review, we describe the incidence of ILD among patients with HER2-positive metastatic breast cancer (MBC) receiving anti-HER2 therapies, and we describe existing recommendations for monitoring and managing drug-induced ILD among these patients. METHODS: We searched PubMed and Embase to identify clinical trials and postmarket observational studies that investigated anti-HER2 therapies for HER2-positive MBC, reported on ILD, and were published during January 1, 2009 to July 15, 2019. Articles were screened by two researchers; data were extracted from the full-text articles. RESULTS: The 18 articles selected for this review assessed 9,886 patients who received trastuzumab (8 articles), lapatinib (4 articles), trastuzumab emtansine (3 articles), trastuzumab deruxtecan (2 articles), or trastuzumab duocarmazine (1 article). The overall incidence of all-grade ILD was 2.4% (n = 234), with 66.7% (n = 156) occurring as grade 1-2 events, 0.5% grade 3-4 (n = 54; incidence), and 0.2% grade 5 (n = 16; incidence). The highest ILD incidence (21.4%) was among patients receiving trastuzumab combined with everolimus and paclitaxel. Ten studies indicated that ILD events were managed via dose interruption, dose reduction, or treatment discontinuation; two studies included detailed guidelines on managing drug-induced ILD. CONCLUSIONS: ILD is a well-described adverse drug reaction associated with several anti-HER2 drugs. Published ILD management guidelines are available for few anti-HER2 treatment regimens; however, guidance for monitoring for anti-HER2 drug-induced ILD is lacking.

Macrophage-derived extracellular vesicles mediate smooth muscle hyperplasia: role of altered miRNA cargo in response to HIV infection and substance abuse.

Our previous studies consistently demonstrate enhanced pulmonary vascular remodeling in HIV-infected intravenous drug users, and in simian immunodeficiency virus-infected macaques or HIV-transgenic rats exposed to opioids or cocaine. Although we reported an associated increase in perivascular inflammation, the exact role of inflammatory cells in the development of pulmonary vascular remodeling remains unknown. In this study, HIV-infected and cocaine (H+C)-treated human monocyte derived macrophages released a higher number of extracellular vesicles (EVs), compared to HIV-infected or uninfected cocaine-treated macrophages, with a significant increase in the particle size range to 100-150 nm. Treatment of primary human pulmonary arterial smooth muscle cells (HPASMCs) with these EVs resulted in a significant increase in smooth muscle proliferation. We also observed a significant increase in the miRNA-130a level in the EVs derived from H+C-treated macrophages that corresponded with the decrease in the expression of phosphatase and tensin homolog and tuberous sclerosis 1 and 2 and activation of PI3K/protein kinase B signaling in HPASMCs on addition of these EVs. Transfection of HPASMCs with antagomir-130a-ameliorated the EV-induced effect. Thus, we conclude that EVs derived from H+C-treated macrophages promote pulmonary smooth muscle proliferation by delivery of its prosurvival miRNA cargo, which may play a crucial role in the development of PAH.-Sharma, H., Chinnappan, M., Agarwal, S., Dalvi, P., Gunewardena, S., O'Brien-Ladner, A., Dhillon, N. K. Macrophage-derived extracellular vesicles mediate smooth muscle hyperplasia: role of altered miRNA cargo in response to HIV infection and substance abuse.

Effect of Cocaine on Pulmonary Vascular Remodeling and Hemodynamics in Human Immunodeficiency Virus-Transgenic Rats.

Human immunodeficiency virus (HIV)-related pulmonary arterial hypertension has been found to be more prevalent in intravenous drug users. Our earlier cell-culture findings reported down-regulation of bone morphogenetic protein receptors (BMPRs) in combination with enhanced proliferation of human pulmonary arterial smooth muscle cells (PASMCs) in the presence of HIV-Trans-activator of transcription (Tat) and cocaine compared with either treatment alone. Here, we report physiologic evidence of significant increases in mean pulmonary arterial pressure in HIV-transgenic (Tg) rats intraperitoneally administered 40 mg/kg body weight cocaine (HIV-cocaine group) once daily for 21 days when compared with HIV-Tg rats given saline (HIV group) or wild-type (WT) Fischer 334 rats treated with (WT-cocaine group) and without cocaine (WT group). In addition, right ventricle systolic pressure was also found to be significantly higher in the HIV-cocaine rats compared with the WT group. Significant down-regulation in protein expression of BMPR-2 and BMPR-1B was observed in total lung extract from HIV-cocaine rats compared with the other three groups. Furthermore, the PASMCs isolated from HIV-cocaine rats demonstrated a higher level of proliferation and lower levels of apoptosis compared with cells isolated from other rat groups. Interestingly, corroborating our earlier cell-culture findings, we observed higher expression of BMPR-2 and BMPR-1B messenger RNA and significantly lower levels of BMPR-2 and BMPR-1B protein in HIV-cocaine PASMCs compared with cells isolated from all other groups. In conclusion, our findings support an additive effect of cocaine and HIV on smooth muscle dysfunction, resulting in enhanced pulmonary vascular remodeling with associated elevation of mean pulmonary arterial pressure and right ventricle systolic pressure in HIV-Tg rats exposed to cocaine.

Ligand-Independent Activation of Platelet-Derived Growth Factor Receptor ß during Human Immunodeficiency Virus-Transactivator of Transcription and Cocaine-Mediated Smooth Muscle Hyperplasia.

Our previous study supports an additive effect of cocaine to human immunodeficiency virus infection in the development of pulmonary arteriopathy through enhancement of proliferation of pulmonary smooth muscle cells (SMCs), while also suggesting involvement of platelet-derived growth factor receptor (PDGFR) activation in the absence of further increase in PDGF-BB ligand. Redox-related signaling pathways have been shown to regulate tyrosine kinase receptors independent of ligand binding, so we hypothesized that simultaneous treatment of SMCs with transactivator of transcription (Tat) and cocaine may be able to indirectly activate PDGFR through modulation of reactive oxygen species (ROS) without the need for PDGF binding. We found that blocking the binding of ligand using suramin or monoclonal IMC-3G3 antibody significantly reduced ligand-induced autophosphorylation of Y1009 without affecting ligand-independent transphosphorylation of Y934 residue on PDGFRß in human pulmonary arterial SMCs treated with both cocaine and Tat. Combined treatment of human pulmonary arterial SMCs with cocaine and Tat resulted in augmented production of superoxide radicals and hydrogen peroxide when compared with either treatment alone. Inhibition of this ROS generation prevented cocaine- and Tat-mediated Src activation and transphosphorylation of PDGFRß at Y934 without any changes in phosphorylation of Y1009, in addition to attenuation of smooth muscle hyperplasia. Furthermore, pretreatment with an Src inhibitor, PP2, also suppressed cocaine- and Tat-mediated enhanced Y934 phosphorylation and smooth muscle proliferation. Finally, we report total abrogation of cocaine- and Tat-mediated synergistic increase in cell proliferation on inhibition of both ligand-dependent and ROS/Src-mediated ligand-independent phosphorylation of PDGFRß.

Downregulation of bone morphogenetic protein receptor axis during HIV-1 and cocaine-mediated pulmonary smooth muscle hyperplasia: implications for HIV-related pulmonary arterial hypertension.

OBJECTIVE: Our previous findings support an additive effect of cocaine to HIV infection in the development of pulmonary arteriopathy through enhanced proliferation of human pulmonary smooth muscle cells. We now examined the role of antiproliferative bone morphogenetic protein receptor (BMPR) axis in HIV protein and cocaine-mediated pulmonary smooth muscle hyperplasia. APPROACH AND RESULTS: Stimulation of BMPR axis resulted in attenuation of synergistic increase in the proliferation of human pulmonary arterial smooth muscle cells in response to cocaine and HIV protein, transactivator of transcription (Tat). Interestingly, an increase in mRNA but decrease in protein levels of BMPR with correlated decrease in the activation of Sma- and MAD-related family protein 1/5/8 and Id1 gene expression was observed on combined treatment with cocaine and Tat when compared with the untreated cells at all time points tested. Although longer exposure to either cocaine or Tat alone also resulted in a significant decrease in the BMPR protein expression, the abrogation on combined treatment was still significantly more when compared with that of the monotreatments. Significant increase in mRNA but downmodulation of BMPR protein expression was also observed in the lung extracts from HIV-infected intravenous drug users (HIV+IVDU) when compared with that from HIV-infected non-IVDUs (HIV) or uninfected IVDUs (IVDU). Furthermore, significant decrease in BMPR protein expression was also observed in HIV or IVDUs when compared with normal controls that correlated with in vitro findings on chronic exposure to cocaine or HIV protein alone. CONCLUSIONS: Simultaneous exposure of pulmonary smooth muscle cells to viral protein(s) and cocaine exacerbates downregulation of BMPR axis that may result in enhanced pulmonary vasculature aberrations in HIV+IVDUs.

Exploring the impact of pediatric short bowel syndrome on parent well-being using a disease-specific pilot survey.

BACKGROUND: Children with short bowel syndrome (SBS) have complex care needs, most of which are met in the home by family caregivers who may experience a range of stressors unique to this experience. Prior research suggests that parents of children with SBS have poorer health-related quality of life than peers parenting children without health needs, but the mechanisms shaping parent outcomes are understudied. METHODS: A pilot survey was developed using a community-driven research design to measure the impact of disease-specific items on parent-perceived well-being. The cross-sectional survey, which included both closed-ended and open-ended items, was distributed to a convenience sample of parents of children with SBS. Quantitative and qualitative data were integrated for a mixed-methods analysis of how individual items impacted parent well-being. RESULTS: Twenty parents completed the survey. Sleep interruptions, lack of support and resources, and psychological stressors and their mental health implications were more frequently reported as stressors than logistics related to caregiving (e.g., managing therapies and preparing specialized meals). CONCLUSION: The impact of a child's SBS on parent well-being may stem mainly from three interconnected domains: poor sleep and its consequences, lack of access to support and resources, and a range of psychological stressors that affect parent mental health. Understanding the mechanisms through which SBS shapes parent well-being is a necessary first step for developing targeted interventions to support parents and provide family-centered care.

Enhanced pulmonary arteriopathy in simian immunodeficiency virus-infected macaques exposed to morphine.

RATIONALE: HIV-associated pulmonary arterial hypertension (PAH) is likely a more prevalent noninfectious complication of AIDS than previously recognized. Furthermore, the majority of HIV-PAH cases occur in individuals with a history of intravenous drug use. In this study we used a simian immunodeficiency (SIV) macaque model and a primary cell-culture system to investigate the association between drug abuse and HIV infection in HIV-PAH development. METHODS: The archival lung tissues from macaques previously used to study the effect of morphine on SIV infection-associated neuropathogenesis were analyzed for pulmonary vascular changes. The direct effect of HIV proteins and illicit drugs was investigated on oxidative stress, survival, and proliferation of human pulmonary microvascular endothelial cells. MEASUREMENTS AND MAIN RESULTS: SIVmacR71/17E-infected rhesus macaques treated with morphine (VM group) demonstrated significant pulmonary vascular remodeling, including the presence of early and advanced complex (plexiform) lesions, when compared with either the SIV-infected (V group) or morphine-treated uninfected (M group) macaques. However, both the V (two of five) and VM (two of six) groups included some animals with Pneumocystis jirovecii pneumonia. The endothelial cells lining the vessels with medial hypertrophy or initial-stage intimal lesions in lung sections from VM macaques demonstrated an increase in positivity for both terminal dUTP nick-end labeling and Ki67. Oxidative stress-mediated enhanced apoptosis followed by enhanced proliferation of endothelial cells was observed on simultaneous treatment with viral proteins and drugs of abuse compared with either treatment alone. CONCLUSIONS: Our findings suggest that SIV/HIV protein(s) and morphine interact to cause the proliferation of apoptosis-resistant endothelial cells leading to angio-obliteration.

A beautiful struggle: Parent-perceived impact of short bowel syndrome on child and family wellbeing.

BACKGROUND: Despite considerable improvements in outcomes for children with short bowel syndrome (SBS), many clinicians remain pessimistic about long-term quality of life (QoL) for this population. METHODS: The validated FaMM tool was used to measure parent-perceived impact of the child's condition on child and family life. Partnered disease-specific survey questions relevant to child's overall wellbeing and family function were additionally completed and reported. The cross-sectional surveys were distributed to a convenience sample of parents of children with SBS. Child and family wellbeing were described and compared across child age group and involvement of an intestinal rehabilitation program (IRP). Multivariate regression analyses investigated associations between outcomes and IRP management. Open-ended responses were analyzed to investigate perceived impact of the child's SBS on the parent. RESULTS: Seventeen parents completed both surveys; 71% perceived child QoL as higher today than what they had originally been told to expect. Child daily life and family difficulty scores suggest parents perceived both to be fairly "normal". While acknowledging effort invested in condition management, parents perceived high competence in managing their child's condition; 56% perceived personal growth resulting from their child's SBS journey. IRP management was associated with better child daily life (4.11, p = 0.015), family difficulty (-4.85, p = 0.048), and family management ability (4.28, p = 0.014) scores. CONCLUSIONS: Many parents perceive child and family life with SBS to be fairly "normal", manage their child's care with great competence, and report personal growth because of their child's SBS journey. Additional research inclusive of diverse patient and parent backgrounds is warranted. LEVEL OF EVIDENCE: prognosis study; Level IV.

Effect of cocaine on human immunodeficiency virus-mediated pulmonary endothelial and smooth muscle dysfunction.

Human immunodeficiency virus (HIV)-associated pulmonary arterial hypertension (PAH) is a devastating, noninfectious complication of acquired immune deficiency syndrome, and the majority of HIV-PAH cases occur in individuals with a history of intravenous drug use (IVDU). However, although HIV-1 and IVDU have been associated with PAH independently or in combination, the pathogenesis of the disproportionate presence of HIV-PAH in association with IVDU has yet to be characterized. The objective of this study was to obtain a better understanding of the interactions between HIV-1 and cocaine to help uncover the mechanism(s) of the development of HIV-PAH. We observed that exposure of HIV-infected macrophages or HIV-Trans-Activator of Transcription (Tat)-treated pulmonary endothelial cells to cocaine enhanced the expression of platelet-derived growth factor (PDGF)-BB. Simultaneous treatment with Tat and cocaine, on the other hand, exacerbated both the disruption of tight junction proteins (TJPs), with enhanced permeability in pulmonary endothelial cells, and the proliferation of pulmonary smooth muscle cells (pSMCs) compared with either treatment alone. Histological examination of HIV plus IVDU human lung sections showed signs of early pulmonary arteriopathy, severe down-modulation of TJPs, and increased expression of PDGF-BB compared with the lung sections from individuals who are infected with HIV and without history of IVDU. Interestingly, blocking of PDGF receptor signaling with the receptor antagonist or small interfering RNA has been shown to inhibit the increase in proliferation of pSMCs on Tat and cocaine exposure. Our results, therefore, support an additive effect of cocaine to HIV infection in the development of pulmonary arteriopathy through enhancement of endothelial dysfunction and proliferation of pSMCs, while also suggesting PDGF-PDGF receptor axis as a potential target for use in clinical intervention.

Hypoxia-inducible factor-1 α/platelet derived growth factor axis in HIV-associated pulmonary vascular remodeling.

BACKGROUND: Human immunodeficiency virus (HIV) infected patients are at increased risk for the development of pulmonary arterial hypertension (PAH). Recent reports have demonstrated that HIV associated viral proteins induce reactive oxygen species (ROS) with resultant endothelial cell dysfunction and related vascular injury. In this study, we explored the impact of HIV protein induced oxidative stress on production of hypoxia inducible factor (HIF)-1α and platelet-derived growth factor (PDGF), critical mediators implicated in the pathogenesis of HIV-PAH. METHODS: The lungs from 4-5 months old HIV-1 transgenic (Tg) rats were assessed for the presence of pulmonary vascular remodeling and HIF-1α/PDGF-BB expression in comparison with wild type controls. Human primary pulmonary arterial endothelial cells (HPAEC) were treated with HIV-associated proteins in the presence or absence of pretreatment with antioxidants, for 24 hrs followed by estimation of ROS levels and western blot analysis of HIF-1α or PDGF-BB. RESULTS: HIV-Tg rats, a model with marked viral protein induced vascular oxidative stress in the absence of active HIV-1 replication demonstrated significant medial thickening of pulmonary vessels and increased right ventricular mass compared to wild-type controls, with increased expression of HIF-1α and PDGF-BB in HIV-Tg rats. The up-regulation of both HIF-1α and PDGF-B chain mRNA in each HIV-Tg rat was directly correlated with an increase in right ventricular/left ventricular+septum ratio. Supporting our in-vivo findings, HPAECs treated with HIV-proteins: Tat and gp120, demonstrated increased ROS and parallel increase of PDGF-BB expression with the maximum induction observed on treatment with R5 type gp-120CM. Pre-treatment of endothelial cells with antioxidants or transfection of cells with HIF-1α small interfering RNA resulted in abrogation of gp-120CM mediated induction of PDGF-BB, therefore, confirming that ROS generation and activation of HIF-1α plays critical role in gp120 mediated up-regulation of PDGF-BB. CONCLUSION: In summary, these findings indicate that viral protein induced oxidative stress results in HIF-1α dependent up-regulation of PDGF-BB and suggests the possible involvement of this pathway in the development of HIV-PAH.

Review of Survival, Safety, and Clinical Outcomes in HER2+ Metastatic Gastric Cancer Following the Administration of Trastuzumab.

BACKGROUND: Therapies targeting human epidermal growth factor receptor 2 (HER2) have become a focus for improving treatment outcomes in patients with gastric cancer. This literature review sought to assesses clinical outcomes, including safety, survival, and treatment outcomes, of patients who received trastuzumab for the treatment of HER2+ metastatic gastric cancer. METHODS: Searches were conducted in PubMed and Embase to identify observational research studies investigating the clinical outcomes of trastuzumab and combination therapies for the treatment of HER2+ metastatic gastric cancer, published January 1, 2014-August 22, 2019. Article screening was a two-phase process, and the results of each screening level were documented in accordance with PRISMA. RESULTS: Twenty articles met the selection criteria for data extraction. Studies focused on treatment patterns or survival, safety, and clinical outcomes, as well as the natural history of disease. In the combined HER2+ patient populations included in this review, tumors were located in the stomach (33.7%), gastroesophageal junction (GEJ, 14.2%), unspecific GEJ or stomach (50.3%), or esophagus (1.9%). Studies observed increases in both overall survival and progression-free survival with the use of trastuzumab-based chemotherapy compared with chemotherapy treatment alone. Additionally, trastuzumab-based chemotherapy appeared to improve survival and clinical outcomes regardless of the presence of multi-organ metastases or tumor location. CONCLUSIONS: Trastuzumab-treated patients have longer survival times than those not treated with trastuzumab and tolerate treatment well, with few serious adverse events. New treatments for second- and subsequent-line therapies would increase regimen options. MINI-ABSTRACT: The treatment patterns and clinical outcomes observed in this literature review suggest patients treated with trastuzumab have longer survival times compared with chemotherapy treatment alone and tolerate treatment.

Down modulation of IFN-gamma signaling in alveolar macrophages isolated from smokers.

The master cytokine, IFN-gamma possesses a wide spectrum of biological effects and is crucial for development of the highly activated macrophage phenotype characteristically found during inflammation. However, no data exists regarding the potential influence of cigarette smoke on the status of the expression of the cell surface receptor for IFN-gamma (IFN-gammaR) on alveolar macrophages (AM) of smokers. Here in, we report reduction in the expression of the IFN-gammaR alpha-chain on AM of cigarette smokers, when compared with non-smokers. Ensuing from the loss of receptor expression on the AM of smokers there was a decrease in IFN-gamma-mediated cell signaling. This included a decrease in the phosphorylation of signal transducer and activator of transcription (STAT)-1 and induction of interferon regulatory factor (IRF)-1. Further, diminished activation/induction of transcription factors did not appear to result from induction of known members of the 'suppressors of cytokine signaling (SOCS)' family. Decreased IFN-gamma signal transduction in AM from smokers may have an important implication regarding the use of therapeutic IFN-gamma in the lungs of patients that develop respiratory disorders as a result of tobacco use.

Agomelatine Drug Utilisation Study in Selected European Countries: A Multinational, Observational Study to Assess Effectiveness of Risk-Minimisation Measures.

BACKGROUND: Hepatotoxic reactions are an important identified risk listed in the agomelatine risk management plan. This post-authorisation safety study evaluated the effectiveness of additional risk-minimisation measures (aRMMs) for agomelatine. OBJECTIVE: The objective of this study was to evaluate, among physicians prescribing agomelatine and their patients, liver function monitoring adherence, compliance with contraindications and patients' reasons for non-compliance with liver monitoring. METHODS: A non-interventional cohort study was conducted among adults initiating agomelatine in routine clinical practice in Denmark, France, Germany and Spain through a retrospective medical record abstraction (MRA) before and after implementation of aRMMs and a cross-sectional patient survey. RESULTS: Fifty-four sites contributed data on 437 and 404 patients in the before- and after-RMM periods, and 237 patients completed the survey. No patient had cirrhosis in either study period; 98.2% of patients in the before- and 98.0% in the after-RMM period had no active liver disease reported at initiation or during treatment. Compliance to contraindicated medications was > 99% in both periods. The adherence to the liver-monitoring regimen was similar in both periods (15.1% before RMM and 16.3% after RMM). In the after-RMM period, 25.2% of patients had a liver test before or at treatment initiation; 61.5% had a liver test during treatment. Among patients surveyed who did not have a blood test before treatment initiation or during treatment, the most frequently cited reason was a test ordered but not yet performed. CONCLUSIONS: The overall adherence to liver-monitoring recommendations remained weakly influenced by aRMMs. However, patients treated with agomelatine are in compliance with relevant contraindications.

Molecular mechanism(s) involved in the synergistic induction of CXCL10 by human immunodeficiency virus type 1 Tat and interferon-gamma in macrophages.

Synergistic interactions between viral proteins and soluble host factors released from infected mononuclear phagocytes play a critical role in the pathogenesis of human immunodeficiency virus (HIV)-associated dementia (HAD). The chemokine CXCL10 has been found to be closely associated with the progression of HIV-1-related central nervous system (CNS) disease and its related neuropsychiatric impairment. In this report the authors demonstrate that the HIV-1 protein Tat can interact with the proinflammatory cytokine interferon (IFN)-gamma to dramatically induce the expression of CXCL10 in macrophages. Synergistic induction of CXCL10 by both Tat and IFN-gamma was susceptible to inhibition by the MEK1/2 inhibitor U0126 and the p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580. In addition, JAK/STAT pathway plays a major role in Tat/gamma-mediated CXCL10 induction in macrophages because pretreatment of stimulated macrophages with JAK inhibitor completely abrogated the synergistic induction of the chemokine. Functionality of the synergistically induced CXCL10 was further demonstrated by its chemotactic activity for peripheral blood lymphocytes. Taken together, these findings demonstrate that the cooperative interaction of Tat and IFN-gamma results in enhanced chemokine expression, which in turn can amplify the inflammatory responses within the CNS of HAD patients by recruiting more lymphocytes in the brain.

Activated protein C attenuates microvascular injury during systemic hypoxia.

In response to hypoxia, an inflammatory cascade is initiated and microvascular injury ensues. Specifically, within 10 min, leukocyte adherence to the endothelium begins, and leukocyte emigration and vascular leak soon follow. Activated protein C (APC) has been reported to have both anticoagulant and anti-inflammatory properties. Activated protein C is best described in its role as a treatment for sepsis. However, it has been used, with some success, in experimental models of hypoxic injury. We hypothesized that APC would be protective against microvascular injury during systemic hypoxia. Randomized prospective animal study. Adult male Sprague-Dawley rats. To characterize the microvascular response to APC exposure during hypoxia, four rat groups were used: saline control, APC infusion alone (100 mg/kg bolus), hypoxia alone (10% O2), and simultaneous hypoxia + APC infusion. Measurements of leukocyte adherence (no. per 100-microm venule), leukocyte emigration (no. per 4,000 microm(2)), and venular leak by fluorescein isothiacyanate-labeled albumin (Fo/Fi) were performed during intravital microscopy of the intact venular bed. Leukocyte adherence decreased from 14.5 (+/-1.2) cells/100-microm venule in hypoxic rats to 4.4 (+/-1.5) cells/100-microm venule in those treated with both hypoxic gas and APC infusion (P < 0.001). Similarly, leukocyte emigration in hypoxic rats reached 12.3 (+/- 2.2) cells/4,000-microm(2) venule, but was reduced to 3.5 (+/-0.3) cells/4,000-microm(2) venule (P <.001). Venular permeability to protein was also significantly decreased in the APC-treated group from 0.82 (+/-0.14) to 0.25 (+/-0.14) (P < 0.001). The infusion of APC attenuates the inflammatory response during systemic hypoxia at the microvascular level, as evidenced by measurements of leukocyte adherence, emigration, and venular permeability. Further investigation is needed to examine the potential role of APC in the treatment of hypoxic injury.

Hyperactive TGF-ß Signaling in Smooth Muscle Cells Exposed to HIV-protein(s) and Cocaine: Role in Pulmonary Vasculopathy.

We earlier demonstrated synergistic increase in the proliferation of pulmonary smooth muscle cells on exposure to HIV-proteins and/or cocaine due to severe down-modulation of bone morphogenetic protein receptor (BMPR) axis: the anti-proliferative arm of TGF-ß super family of receptors. Here, now we demonstrate the effect of HIV-Tat and cocaine on the proliferative TGF-ß signaling cascade. We observed a significant increase in the secretion of TGF-ß1 ligand along with enhanced protein expression of TGFß Receptor (TGFßR)-1, TGFßR-2 and phosphorylated SMAD2/3 in human pulmonary arterial smooth muscle cells on treatment with cocaine and Tat. Further, we noticed an increase in the levels of p-TAK1 complexed with TGFßR-2. Concomitant to this a significant increase in the activation of TAK1-mediated, SMAD-independent downstream signaling molecules: p-MKK4 and p-JNK was observed. However, activation of MKK3/6-p38MAPK, another axis downstream of TAK1 was found to be reduced due to attenuation in the protein levels of BMPR2. Both SMAD and non-SMAD dependent TGFßR cascades were found to contribute to hyper-proliferation. Finally the increase in the levels of phosphorylated TGFßR1 and TGFßR2 on exposure to HIV-proteins and cocaine was confirmed in pulmonary smooth muscle cells from cocaine injected HIV-transgenic rats and in total lung extracts from HIV infected cocaine and/or opioid users.

Enhanced autophagy in pulmonary endothelial cells on exposure to HIV-Tat and morphine: Role in HIV-related pulmonary arterial hypertension.

Intravenous drug use is one of the major risk factors for HIV-infection in HIV-related pulmonary arterial hypertension patients. We previously demonstrated exaggerated pulmonary vascular remodeling with enhanced apoptosis followed by increased proliferation of pulmonary endothelial cells on simultaneous exposure to both opioids and HIV protein(s). Here we hypothesize that the exacerbation of autophagy may be involved in the switching of endothelial cells from an early apoptotic state to later hyper-proliferative state. Treatment of human pulmonary microvascular endothelial cells (HPMECs) with both the HIV-protein Tat and morphine resulted in an oxidative stress-dependent increase in the expression of various markers of autophagy and formation of autophagosomes when compared to either Tat or morphine monotreatments as demonstrated by western blot, transmission electron microscopy and immunofluorescence. Autophagy flux experiments suggested increased formation rather than decreased clearance of autolysosomes. Inhibition of autophagy resulted in a significant increase in apoptosis and reduction in proliferation of HPMECs with combined morphine and Tat (M+T) treatment compared to monotreatments whereas stimulation of autophagy resulted in opposite effects. Significant increases in the expression of autophagy markers as well as the number of autophagosomes and autolysosomes was observed in the lungs of SIV-infected macaques and HIV-infected humans exposed to opioids. Overall our findings indicate that morphine in combination with viral protein(s) results in the induction of autophagy in pulmonary endothelial cells that may lead to an increase in severity of angio-proliferative remodeling of the pulmonary vasculature on simian and human immunodeficiency virus infection in the presence of opioids.

HIV-1/cocaine induced oxidative stress disrupts tight junction protein-1 in human pulmonary microvascular endothelial cells: role of Ras/ERK1/2 pathway.

Intravenous drug use (IVDU) is the major risk factor in the development of HIV-related pulmonary arterial hypertension (HRPAH); however, the pathogenesis of HRPAH in association with IVDU has yet to be characterized. Endothelial injury is considered to be an initiating factor for pulmonary vascular remodeling in animal models of PAH. Our previous study shows that simultaneous exposure to HIV-Trans-activator of transcription (Tat) and cocaine exacerbates both disruption of tight junction proteins and permeability of human pulmonary artery endothelial cells compared with either treatment alone. We here now demonstrate that this HIV-Tat and cocaine mediated endothelial dysfunction accompanies with increase in hydrogen peroxide and superoxide radicals generation and involves redox sensitive signaling pathway. Pretreatment with antioxidant cocktail attenuated the cocaine and Tat mediated disassembly of Zonula Occludens (ZO)-1 and enhancement of endothelial monolayer permeability. Furthermore, inhibition of NADPH oxidase by apocynin or siRNA-mediated knockdown of gp-91(phox) abolished the Tat/cocaine-induced reactive oxygen species (ROS) production, suggesting the NADPH oxidase mediated generation of oxidative radicals. In addition, ROS dependent activation of Ras and ERK1/2 Kinase was observed to be mediating the TJP-1 disassembly, and endothelial dysfunction in response to cocaine and Tat exposure. In conclusion, our findings demonstrate that Tat/cocaine -mediated production of ROS activate Ras/Raf/ERK1/2 pathway that contributes to disruption of tight junction protein leading to pulmonary endothelial dysfunction associated with pulmonary vascular remodeling.