University of California San Francisco

Department of Anesthesia and Perioperative Care

1.

Wilhelmsen K, Khakpour S, Tran A, Sheehan K, Schumacher M, Xu F, Hellman J. The Endocannabinoid/Endovanilloid N-Arachidonoyl Dopamine (NADA) and Synthetic Cannabinoid WIN55,212-2 Abate the Inflammatory Activation of Human Endothelial Cells. J Biol Chem. 2014 May 9;289(19):13079-100. (IF: 4.651)

During health endothelial cells maintain vascular homeostasis, and mediate critical aspects of the host’s innate immune response to infection. It is widely believed that during sepsis and inflammatory critical illness, endothelial cell dysfunction contributes to systemic inflammation, and to the coagulopathy, vascular leak, and excessive neutrophil activity that promote organ failure and death. The endogenous cannabinoid system, discovered in the 1990’s has been postulated to maintain homeostasis in a variety of systems. Endogenously produced cannabinoids (endocannabinoids) are derived from arachidonic acid, and are ligands for the cannabinoid receptors 1 and 2 (CB1R and CB2R) and for the transient receptor potential channel V1 (TRPV1). Several endocannabinoids have been reported to modulate aspects of leukocyte inflammatory responses, but thus far the role of the endothelial endocannabinoid system during inflammation has not been thoroughly assessed. We report that endothelial cells express CBRs, TRPV1, and endocannabinoid metabolic enzymes, and that the endocannabinoid N-arachidonoyl dopamine (NADA) and synthetic cannabinoid WIN55,212-2, but not anandamide (AEA) nor 2-arachidonoylglycerol (2-AG), reduce endothelial cell secretion of cytokines and expression of adhesion molecules, and decrease neutrophil adherence to endothelial cell monolayers activated by TNFa, endotoxin or bacterial lipopeptides. We observed that the effects of NADA on the inflammatory activation of endothelial cells are attenuated by CBR antagonists and augmented by TRPV1 antagonists. These data suggest that NADA constrains the endothelial cell inflammatory response through opposing actions at CBRs and TRPV1. Our study suggests that the endothelial endocannabinoid system may play an important role in the resolution of endothelial inflammation, and thus could potentially be targeted to ameliorate inflammatory critical illness.

2.

Chen W, Sun Z, Han Z, Jun K, Camus M, Wankhede M, Mao L, Arnold T, Young WL, Su H. De novo cerebrovascular malformation in the adult mouse after endothelial Alk1 deletion and angiogenic stimulation. Stroke. 2014 Mar;45(3):900-2. (IF: 6.018)

Brain arteriovenous malformation (bAVM) is an important risk factor for intracranial hemorrhage, especially in children and young adults, and the factors contributing to its formation have not been identified. In humans, a deficiency of activin receptor-like kinase 1 (Alk1) causes type 2 hereditary hemorrhagic telangiectasia (HHT2). HHT2 patients can have AVMs in multiple organs, including the brain, and the bAVM phenotype in those patients is similar to that of sporadic bAVM. To identify gene mutation, in which cell types will trigger bAVM formation, we used an HHT2 mouse model and deleted Alk1 in different cell types using a conditional gene knockout strategy. We found that deletion of the Alk1 gene in endothelial cells is essential in initiating de novo bAVM formation.

3.

McAuley DF, Curley GF, Hamid UI, Laffey JG, Abbott J, McKenna DH, Fang X, Matthay MA, Lee JW. Clinical grade allogeneic human mesenchymal stem cells restore alveolar fluid clearance in human lungs rejected for transplantation. American journal of physiology. Lung cellular and molecular physiology. 2014;306(9):L809-815. (IF: 4.04)

The need to increase the donor pool for lung transplantation is a major public health issue. Recently, a new technique of ex vivo lung perfusion (EVLP) has been developed to extend the donor pool size. EVLP allows “rehabilitation” of marginal donor lungs initially rejected for transplantation by allowing a short duration of perfusion and oxygenation with ventilation prior to transplantation. EVLP has also become an ideal method to test the effects of pharmacologic and/or gene- or cell-based therapy prior to surgery to improve the success of lung transplantation. Using an ex vivo human lung preparation, the current studies were designed to determine if intravenous clinical-grade human mesenchymal stem cells (MSC) would be effective in restoring AFC in donor lungs that had been deemed unsuitable for transplantation; impaired AFC contributes to primary graft dysfunction, a major cause of morbidity and mortality after lung transplantation in the form of non-cardiogenic pulmonary edema. The human lungs were perfused with 5% albumin in a balanced electrolyte solution and oxygenated with continuous positive airway pressure. Baseline AFC was measured in the control lobe and if AFC was impaired (defined as <10%/h), the lungs received either 5 × 106 MSC added to the perfusate or perfusion only as a control. AFC was measured in a different lung lobe at 4 h. Intravenous administration of human MSC restored AFC in the injured lungs to a normal level, an effect that was dependent on MSC secretion of keratinocyte growth factor. In contrast, perfusion only did not increase AFC. In summary, administration of allogeneic human MSC was effective in restoring the capacity of the alveolar epithelium to remove pulmonary edema fluid at a normal rate, further rehabilitating marginal donor lungs and potentially developing a technique to increase donor pool size.

4.

Lee BH, Chan JT, Kraeva E, Peterson K, Sall JW. Isoflurane exposure in newborn rats induces long-term cognitive dysfunction in males but not females. Neuropharmacology. 2014;83:9-17. (IF: 4.819)

In a recently published human and animal study we noted a possible difference in cognitive outcome between male and female children that were exposed to anesthesia at an early age (Stratmann et al, Neuropsychopharmacology 2014). This finding was further investigated using a rat model of isoflurane exposure on day of life seven. All anesthesia exposed groups showed the expected increase in brain cell death with no difference by sex. One month later using a series of 4 increasingly difficult object recognition/association tasks we found isoflurane exposed males impaired in 3 of the 4 tasks, while females were not impaired in any task. In further testing, all animals showed appropriate social interaction, but isoflurane exposed males were impaired in social recognition. These findings suggest that males may have a greater risk of cognitive impairment after early life anesthesia exposure and that brain cell death which was similar between groups is likely not the primary cause for the deficits we observed. http://www.sciencedirect.com/science/article/pii/S0028390814001063

5.

Zavala K, Lee J, Chong J, Sharma M, Eilers H, Schumacher MA. The anticancer antibiotic mithramycin-A inhibits TRPV1 expression in dorsal root ganglion neurons. Neurosci Lett. 2014 Aug 22;578:211-6. doi: 10.1016/j.neulet.2014.01.021. Epub 2014 Jan 25.

PMID: 24468003

Estimates of the number of individuals suffering from chronic pain in the United States and its physical, emotional and financial toll are staggering. Although tremendous clinical advances have been made, our ability to prevent or reverse the development of chronic pain states remains a largely unresolved clinical challenge. Activation of peripheral nociceptors by products of inflammation has been shown to be dependent on specific sensory transducing elements such as the capsaicin receptor, TRPV1. Transient receptor potential vanilloid type -1 (TRPV1) directs complex roles in signal transduction including the detection of noxious stimuli arising from cellular injury and inflammation. One line of investigation has been related to understanding the consequence of TRPV1 up-regulation in sensory neurons under chronic pathophysiologic conditions such as inflammation or nerve injury. Within this context, we have serendipitously determined that the principal promoter for the capsaicin receptor (TRPV1) contains a GC-box binding motif within promoter P2 that is essential for TRPV1 transcriptional activity. A search for small-molecule inhibitors acting at GC-box motifs revealed the anticancer agent mithramycin-A (plicamycin) an aureolic acid polyketide produced by a species of the soil bacterium Streptomyces. Mithramycin-A has been described as having its anticancer / antiproliferative effect through binding to GC- and / or GT-box DNA binding motifs and either displacing or preventing the binding of transcription factors that utilize GC-box motifs within their promoter site. Based on our model of Sp1 and Sp4 binding to the GC-box domain within the rTRPV1 promoter region, we tested whether the small molecule, mithramcyin-A, would alter endogenous TRPV1 expression in cultured rat primary sensory neurons. Mithramycin-A dose-dependently (10-50nM) decreased endogenous TRPV1 mRNA content and appeared to decrease TRPV1-like protein expression in DRG neurons. We also observed that mithramycin-A directed a decrease in the number of capsaicin-responsive DRG neurons without a significant change in the capsaicin-response magnitudes. Interestingly, mithramycin-A also reduced the mRNA encoding Sp1 and Sp4 in DRG neurons, transcription factors previously found to positively regulate TRPV1 expression in sensory neurons. Taken together Mithramycin-A blocks expression of TRPV1 in cultured DRG neurons and may serve as a model for the development of transcriptional inhibitors in chronic pain therapeutics.

Comment on:

6.

Guan Z, Kuhn JA, Wang X, Colquitt B, Solorzano C, Vaman S, Guan AK, Evans-Reinsch Z, Braz J, Devor M, Abboud-Werner SL, Lanier LL, Lomvardas S, Basbaum AI. Injured sensory neuron-derived CSF1 induces microglial proliferation and DAP12-dependent pain. Nat Neurosci. 2016 Jan;19(1):94-101. doi: 10.1038/nn.4189. Epub 2015 Dec 7.

Although microglia have been implicated in nerve injury-induced neuropathic pain, the manner by which injured sensory neurons engage microglia remains unclear. We found that peripheral nerve injury induced de novo expression of colony-stimulating factor 1 (CSF1) in injured sensory neurons. CSF1 was transported to the spinal cord, where it targeted the microglial CSF1 receptor (CSF1R). Cre-mediated sensory neuron deletion of Csf1 completely prevented nerve injury-induced mechanical hypersensitivity and reduced microglial activation and proliferation. In contrast, intrathecal injection of CSF1 induced mechanical hypersensitivity and microglial proliferation. Nerve injury also upregulated CSF1 in motoneurons, where it was required for ventral horn microglial activation and proliferation. Downstream of CSF1R, we found that the microglial membrane adaptor protein DAP12 was required for both nerve injury- and intrathecal CSF1-induced upregulation of pain-related microglial genes and the ensuing pain, but not for microglial proliferation. Thus, both CSF1 and DAP12 are potential targets for the pharmacotherapy of neuropathic pain.

7.

Lawton SK, Xu F, Tran A, Wong E, Prakash A, Schumacher M, Hellman J, Wilhelmsen K. N-Arachidonoyl Dopamine Modulates Acute Systemic Inflammation via Nonhematopoietic TRPV1. J Immunol. 2017 Aug 15;199(4):1465-1475. doi: 10.4049/jimmunol.1602151. Epub 2017 Jul 12.

N-Arachidonoyl dopamine (NADA) is an endogenous lipid that potently activates the transient receptor potential vanilloid 1 (TRPV1), which mediates pain and thermosensation. NADA is also an agonist of cannabinoid receptors 1 and 2. We have reported that NADA reduces the activation of cultured human endothelial cells by LPS and TNF-α. Thus far, in vivo studies using NADA have focused on its neurologic and behavioral roles. In this article, we show that NADA potently decreases in vivo systemic inflammatory responses and levels of the coagulation intermediary plasminogen activator inhibitor 1 in three mouse models of inflammation: LPS, bacterial lipopeptide, and polymicrobial intra-abdominal sepsis. We also found that the administration of NADA increases survival in endotoxemic mice. Additionally, NADA reduces blood levels of the neuropeptide calcitonin gene-related peptide but increases the neuropeptide substance P in LPS-treated mice. We demonstrate that the anti-inflammatory effects of NADA are mediated by TRPV1 expressed by nonhematopoietic cells and provide data suggesting that neuronal TRPV1 may mediate NADA's anti-inflammatory effects. These results indicate that NADA has novel TRPV1-dependent anti-inflammatory properties and suggest that the endovanilloid system might be targeted therapeutically in acute inflammation.

8.

Liu J, Kuwabara A, Kamio Y, Hu S, Park J, Hashimoto T, Lee JW. Human Mesenchymal Stem Cell-Derived Microvesicles Prevent the Rupture of Intracranial Aneurysm in Part by Suppression of Mast Cell Activation via a PGE2-Dependent Mechanism. Stem Cells. 2016 Dec;34(12):2943-2955. doi: 10.1002/stem.2448. Epub 2016 Jul 8.

Activation of mast cells participates in the chronic inflammation associated with cerebral arteries in intracranial aneurysm formation and rupture. Several studies have shown that the anti-inflammatory effect of mesenchymal stem cells (MSCs) is beneficial for the treatment of aneurysms. However, some long-term safety concerns exist regarding stem cell-based therapy for clinical use. We investigated the therapeutic potential of microvesicles (MVs) derived from human MSCs, anuclear membrane bound fragments with reparative properties, in preventing the rupture of intracranial aneurysm in mice, particularly in the effect of MVs on mast cell activation. Intracranial aneurysm was induced in C57BL/6 mice by the combination of systemic hypertension and intrathecal elastase injection. Intravenous administration of MSC-derived MVs on day 6 and day 9 after aneurysm induction significantly reduced the aneurysmal rupture rate, which was associated with reduced number of activated mast cells in the brain. A23187-induced activation of both primary cultures of murine mast cells and a human mast cell line, LAD2, was suppressed by MVs treatment, leading to a decrease in cytokine release and tryptase and chymase activities. Upregulation of prostaglandin E2 (PGE2) production and E-prostanoid 4 (EP4) receptor expression were also observed on mast cells with MVs treatment. Administration of an EP4 antagonist with the MVs eliminated the protective effect of MVs against the aneurysmal rupture in vivo. Human MSC-derived MVs prevented the rupture of intracranial aneurysm, in part due to their anti-inflammatory effect on mast cells, which was mediated by PGE2 production and EP4 activation.

9.

Received New York Times coverage:

London MJ, Schwartz GG, Hur K, Henderson WG. Association of Perioperative Statin Use With Mortality and Morbidity After Major Noncardiac Surgery. JAMA Intern Med. 2017 Feb 1;177(2):231-242. doi: 10.1001/jamainternmed.2016.8005.

Importance: The efficacy of statins in reducing perioperative cardiovascular and other organ system complications in patients undergoing noncardiac surgery remains controversial. Owing to a paucity of randomized clinical trials, analyses of large databases may facilitate informed hypothesis generation and more efficient trial design.

Objective: To evaluate associations of early perioperative statin use with outcomes in a national cohort of veterans undergoing noncardiac surgery.

Design, Setting, and Participants: This retrospective, observational cohort analysis included 180 478 veterans undergoing elective or emergent noncardiac surgery (including vascular, general, neurosurgery, orthopedic, thoracic, urologic, and otolaryngologic) who were admitted within 7 days of surgery and sampled by the Veterans Affairs Surgical Quality Improvement Program (VASQIP). Patients were admitted to Department of Veterans Affairs hospitals and underwent 30-day postoperative follow-up. Data were collected from October 1, 2005, to September 30, 2010, and analyzed from November 28, 2013, to October 31, 2016.

Exposure: Statin use on the day of or the day after surgery.

Main Outcomes and Measures: All-cause 30-day mortality (primary outcome) and standardized 30-day cardiovascular and noncardiovascular outcomes captured by VASQIP. Use of statins and other perioperative cardiovascular medications was ascertained from the Veterans Affairs Pharmacy Benefits Management research database.

Results: A total of 180 478 eligible patients (95.6% men and 4.4% women; mean [SD] age, 63.8 [11.6] years) underwent analysis, and 96 486 were included in the propensity score-matched cohort (96.3% men; 3.7% women; mean [SD] age, 65.9 [10.6] years). At the time of hospital admission, 37.8% of patients had an active outpatient prescription for a statin, of whom 80.8% were prescribed simvastatin and 59.5% used moderate-intensity dosing. Exposure to a statin on the day of or the day after surgery based on an inpatient prescription was noted in 31.5% of the cohort. Among 48 243 propensity score-matched pairs of early perioperative statin-exposed and nonexposed patients, 30-day all-cause mortality was significantly reduced in exposed patients (relative risk, 0.82; 95% CI, 0.75-0.89; P < .001; number needed to treat, 244; 95% CI, 170-432). Of the secondary outcomes, a significant association with reduced risk of any complication was noted (relative risk, 0.82; 95% CI, 0.79-0.86; P < .001; number needed to treat, 67; 95% CI, 55-87); all were significant except for the central nervous system and thrombosis categories, with the greatest risk reduction (relative risk, 0.73; 95% CI, 0.64-0.83) for cardiac complications.

Conclusions and Relevance: Early perioperative exposure to a statin was associated with a significant reduction in all-cause perioperative mortality and several cardiovascular and noncardiovascular complications. However, the potential for selection biases in these results must be considered.

10.

Weinsheimer S, Bendjilali N, Nelson J, Guo DE, Zaroff JG, Sidney S, McCulloch CE, Al-Shahi Salman R, Berg JN, Koeleman BP, Simon M, Bostroem A, Fontanella M, Sturiale CL, Pola R, Puca A, Lawton MT, Young WL, Pawlikowska L, Klijn CJ, Kim H; GEN-AVM Consortium. Genome-wide association study of sporadic brain arteriovenous malformations. J Neurol Neurosurg Psychiatry. 2016 Sep;87(9):916-23. doi: 10.1136/jnnp-2015-312272. Epub 2016 Jan 27.

BACKGROUND: The pathogenesis of sporadic brain arteriovenous malformations (BAVMs) remains unknown, but studies suggest a genetic component. We estimated the heritability of sporadic BAVM and performed a genome-wide association study (GWAS) to investigate association of common single nucleotide polymorphisms (SNPs) with risk of sporadic BAVM in the international, multicentre Genetics of Arteriovenous Malformation (GEN-AVM) consortium.

METHODS: The Caucasian discovery cohort included 515 BAVM cases and 1191 controls genotyped using Affymetrix genome-wide SNP arrays. Genotype data were imputed to 1000 Genomes Project data, and well-imputed SNPs (>0.01 minor allele frequency) were analysed for association with BAVM. 57 top BAVM-associated SNPs (51 SNPs with p<10(-05) or p<10(-04) in candidate pathway genes, and 6 candidate BAVM SNPs) were tested in a replication cohort including 608 BAVM cases and 744 controls.

RESULTS: The estimated heritability of BAVM was 17.6% (SE 8.9%, age and sex-adjusted p=0.015). None of the SNPs were significantly associated with BAVM in the replication cohort after correction for multiple testing. 6 SNPs had a nominal p<0.1 in the replication cohort and map to introns in EGFEM1P, SP4 and CDKAL1 or near JAG1 and BNC2. Of the 6 candidate SNPs, 2 in ACVRL1 and MMP3 had a nominal p<0.05 in the replication cohort.

CONCLUSIONS: We performed the first GWAS of sporadic BAVM in the largest BAVM cohort assembled to date. No GWAS SNPs were replicated, suggesting that common SNPs do not contribute strongly to BAVM susceptibility. However, heritability estimates suggest a modest but significant genetic contribution.

11.

Received coverage in the New York Times and Reuters Whitlock EL, Diaz-Ramirez LG, Glymour MM, Boscardin WJ, Covinsky KE, Smith AK. Association Between Persistent Pain and Memory Decline and Dementia in a Longitudinal Cohort of Elders. JAMA Intern Med. 2017 Aug 1;177(8):1146-1153. doi: 10.1001/jamainternmed.2017.1622.

Importance: Chronic pain is common among the elderly and is associated with cognitive deficits in cross-sectional studies; the population-level association between chronic pain and longitudinal cognition is unknown.

Objective: To determine the population-level association between persistent pain, which may reflect chronic pain, and subsequent cognitive decline.

Design, Setting, and Participants: Cohort study with biennial interviews of 10 065 community-dwelling older adults in the nationally representative Health and Retirement Study who were 62 years or older in 2000 and answered pain and cognition questions in both 1998 and 2000. Data analysis was conducted between June 24 and October 31, 2016.

Exposures: "Persistent pain," defined as a participant reporting that he or she was often troubled with moderate or severe pain in both the 1998 and 2000 interviews.

Main Outcomes and Measures: Coprimary outcomes were composite memory score and

dementia probability, estimated by combining neuropsychological test results and informant and proxy interviews, which were tracked from 2000 through 2012. Linear mixed-effects models, with random slope and intercept for each participant, were used to estimate the association of persistent pain with slope of the subsequent cognitive trajectory, adjusting for demographic characteristics and comorbidities measures in 2000 and applying sampling weights to represent the 2000 US population. We hypothesized that persistent pain would predict accelerated memory decline and increased probability of dementia. To quantify the impact of persistent pain on functional independence, we combined our primary results with information on the association between memory and ability to manage medications and finances independently.

Results: Of the 10 065 eligible HRS sample members, 60% were female, and median baseline age was 73 years (interquartile range, 67-78 years). At baseline, persistent pain affected 10.9% of participants and was associated with worse depressive symptoms and more limitations in activities of daily living. After covariate adjustment, persistent pain was associated with 9.2% (95% CI, 2.8%-15.0%) more rapid memory decline compared with those without persistent pain. After 10 years, this accelerated memory decline implied a 15.9% higher relative risk of inability to manage medications and an 11.8% higher relative risk of inability to manage finances independently. Adjusted dementia probability increased 7.7% faster (95% CI, 0.55%-14.2%); after 10 years, this translates to an absolute 2.2% increase in dementia probability for those with persistent pain.

Conclusions and Relevance: Persistent pain was associated with accelerated memory decline and increased probability of dementia.